Tachykinin antagonists

ABSTRACT

The invention concerns tachykinin antagonists. The compounds are nonpeptides which have utility in treating disorders mediated by tachykinins. Such disorders are respiratory, inflammatory, gastrointestinal, ophthalmic, allergies, pain, vascular, diseases of the central nervous system, and migraine. Methods of preparing compounds and novel intermediates are also included. The compounds are expected to be especially useful in asthma and rheumatoid arthritis.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No. 08/953,037 filed Oct. 17, 1997, now U.S. Pat. No. 5,856,354 which is a divisional of U.S. patent application Ser. No. 08/727,067 filed Oct. 8, 1996, now U.S. Pat. No. 5,716,979; which is a divisional of U.S. patent application Ser. No. 08/344,064 filed Nov. 29, 1994, now U.S. Pat. No. 5,594,022; and is a continuation-in-part of U.S. patent application Ser. No. 08/097,264, filed Jul. 23, 1993, now abandoned; and is a continuation-in-part of U.S. application Ser. No. 07/930,252, filed Aug. 13, 1992, now abandoned.

BACKGROUND OF THE INVENTION

Over the last decade, major advances have been made in the understanding of the biology of the mammalian tachykinin neuropeptides. It is now well established that substance-P (1), neurokinin A (NKA) (2), and neurokinin B (NKB) (3), all of which share a common C-terminal sequence Phe-X-Gly-Leu-Met-NH₂, (Nakanishi S, Physiol Rev 1987;67:117), are widely distributed throughout the periphery and central nervous system (CNS) where they appear to interact with at least three receptor types referred to as NK₁, NK₂, and NK₃, (Guard S, et al., Neurosci Int 1991;18:149). Substance-P displays highest affinity for NK₁ receptors, whereas NKA and NKB bind preferentially to NK₂ and NK₃ receptors, respectively. Recently, all three receptors have been cloned and sequenced and shown to be members of the G-protein-linked "super family" of receptors (Nakanishi S, Annu Rev Neurosci 1991;14:123). A wealth of evidence supports the involvement of tachykinin neuropeptides in a variety of biological activities including pain transmission, vasodilation, smooth muscle contraction, bronchoconstriction, activation of the immune system (inflammatory pain), and neurogenic inflammation (Pernow B, Pharmacol Rev 1983;35:85). However, to date, a detailed understanding of the physiological roles of tachykinin neuropeptides has been severely hampered by a lack of selective, high affinity, metabolically stable tachykinin receptor antagonists that possess both good bioavailability and CNS penetration. Although several tachykinin receptor antagonists have been described (Tomczuk B E, et al., Current Opinions in Therapeutic Patents 1991;1:197), most have been developed through the modification and/or deletion of one or more of the amino acids that comprise the endogenous mammalian tachykinins such that the resulting molecules are still peptides that possess poor pharmacokinetic properties and limited in vivo activities.

However, since 1991, a number of high-affinity nonpeptide antagonists have been reported. Snider R M, et al, (Science 1991;251:435), and Garret C, et. al, (Proc Natl Acad Sci 1991;88:10208), described CP-96,345 and RP 67580, respectively, as antagonists at the NK₁ receptor, while Advenier C, et al., (Brit J Pharmacol 1992;105:78), presented data on SR 48969 showing its high affinity and selectivity for NK₂ receptors. It is of interest that most of the nonpeptide tachykinin receptor antagonists described to date arose, either directly or indirectly, out of the screening of large compound collections using a robust radioligand binding assay as the primary screen. Recently, FK 888, a "dipeptide" with high affinity for the NK₁ receptor was described (Fujii J, et al., Neuropeptide 1992;22:24).

International Publication Numbers WO 93/01169, WO 93/01165, and WO 93/001160 cover certain nonpeptide tachykinin receptor antagonists.

Substance-P is widely distributed throughout the periphery and central nervous system. It is believed to mediate a variety of biological actions, via an interaction with three receptor types referred to as NK₁, NK₂, and NK₃, including smooth muscle contraction, pain transmission, neuronal excitation, secretion of saliva, angiogenesis, broncho-constriction, activation of the immune system and neurogenic inflammation.

Accordingly, compounds capable of antagonizing the effects of substance-P at NK₁ receptors will be useful in treating or preventing a variety of brain disorders including pain, anxiety, panic, depression, schizophrenia, neuralgia, and addiction disorders; inflammatory diseases such as arthritis, asthma, and psoriasis; gastrointestinal disorders including colitis, Crohn's disease, irritable bowel syndrome, and satiety; allergic responses such as eczema and rhinitis; vascular disorders such as angina and migraine; neuropathological disorders including Parkinson's disease, multiple sclerosis, and Alzheimer's disease; and ophthalmic diseases including scleroderma.

The compounds of the invention, NK₁ receptor antagonists, are useful as anti-angiogenic agents for the treatment of conditions associated with aberrant neovascularization such as rheumatoid arthritis, atherosclerosis, and tumor cell growth. They will also be useful as agents for imaging NK₁ receptors in vivo in conditions such as ulcerative colitis and Crohn's disease.

SUMMARY OF THE INVENTION

The invention covers tachykinin antagonists. The compounds are nonpeptides which have proved to be highly selective and functional tachykinin antagonists. These compounds are unique in the alkylation/substitution pattern along their back bone.

Compounds of the invention are those of formula ##STR1## or a pharmaceutically acceptable salt thereof wherein R is phenyl,

pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted,

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

NO₂,

halogen,

NH₂, or

CF₃ ;

R¹ and R² are each independently hydrogen or alkyl of from 1 to 4 atoms;

R and R², when joined by a bond, can form a ring;

X is ##STR2## wherein R¹¹ is hydrogen or alkyl of from 1 to 3 carbon atoms; R³ is hydrogen or (CH₂)_(m) R¹³ where m is an integer of from 1 to 6 and R¹³ is H, CN, NH₂, N(CH₃)₂, or NHCOCH₃ ;

n is an integer of from 1 to 2;

R⁸ is phenyl,

pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted, or

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

NO₂,

halogen,

NH₂, or

CF₃ ;

Y is ##STR3## wherein R⁴ is hydrogen or alkyl of from 1 to 3 carbon atoms, --CO₂ --,

--COCH₂ --,

--CH₂ O--,

--CH₂ NH--,

--CH═CH--,

--CH₂ CH₂ --,

--CHOHCH₂ --, ##STR4## wherein B is nitrogen, CH, CH₂, oxygen, or sulfur, D is; nitrogen, oxygen, or sulfur, E is nitrogen or CH, CH₂, p is an integer of from 3 to 4, and the dotted lines indicates a double or single bond;

R⁵ and R⁷ are each independently hydrogen or alkyl of from 1 to 4 carbon atoms;

q is an integer of from 0 to 1; and

R⁶ is phenyl,

pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted, or

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

halogen,

NH₂, or

CF₃ ;

straight alkyl of from 1 to 8 carbons, branched alkyl of from 3 to 8 carbons, cycloalkyl of from 5 to 8 carbons, or heterocycloalkyl.

Other cyclic derivatives of Formula I are contemplated such as would occur to one skilled in the art.

Prodrugs of the above are also contemplated such as would occur to one skilled in the art, see Bundgaard, et al., Acta Pharm Suec, 1987;24:23:1-246. For example, where a suitable moiety has been attached to the linker X or Y or the indole N.

Preferred compounds of the invention are those of Formula I above wherein

R is pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted,

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

halogen,

NH₂, or

CF₃ ;

R¹ and R² are each independently hydrogen or alkyl of from 1 to 4 atoms;

R and R², when joined by a bond, can form a ring;

X is ##STR5## wherein R¹¹ is hydrogen or alkyl of from 1 to 3 carbon atoms; R³ is hydrogen or (CH₂)_(m) R¹³ where m is an integer of from 1 to 6 and R¹³ is H, CN, NH₂, N(CH₃)₂, or NHCOCH₃ ;

n is an integer of from 1 to 2;

R⁸ is phenyl,

pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted, or

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

halogen,

NH₂, or

CF₃ ;

Y is ##STR6## wherein R⁴ is hydrogen or alkyl of from 1 to 3 carbon atoms, --CO₂ --,

--COCH₂ --,

--CH₂ O--,

--CH₂ NH--,

--CH═CH--,

--CH₂ CH₂ --,

--CHOHCH₂ --, ##STR7## wherein B is nitrogen, CH, CH₂, oxygen, or sulfur, D is nitrogen, oxygen, or sulfur, E is nitrogen, CH, CH₂, p is an integer of from 3 to 4, and the dotted line indicates a double or single bond;

R⁵ and R⁷ are each independently hydrogen or alkyl of from 1 to 4 carbon atoms;

q is an integer of from 0 to 1; and

R⁶ is phenyl,

pyridine,

thiophene,

furan,

naphthalene,

indole,

benzofuran, or

benzothiophene each unsubstituted, or

mono-, di-, or trisubstituted by

alkyl,

hydroxy,

alkoxy,

NO₂,

halogen,

NH₂, or

CF₃ ;

straight alkyl of from 1 to 8 carbons, branched alkyl of from 3 to 8 carbons, cycloalkyl of from 5 to 8 carbons, or heterocycloalkyl;

More preferred compounds of the invention are those of Formula I above wherein

R is phenyl

pyridyl,

thiophene,

furan,

naphthalene,

indole each unsubstituted, or

mono- or disubstituted by alkyl of 1 to

3 carbons, methoxy, ethoxy, chlorine,

fluorine, NH₂, or CF₃ ;

R¹ and R² are each independently selected from hydrogen and methyl;

X is ##STR8## wherein R¹¹ is hydrogen or methyl; R³ is hydrogen or (CH₂)_(m) R¹³ where m is an integer of from 1 to 6 and R¹³ is H, CN, NH₂, N(CH₃)₂, or NHCOCH₃ ;

n is 1;

R⁸ is phenyl,

naphthyl,

indole, or

benzothiophene;

Y is ##STR9## wherein R⁴ is hydrogen or methyl --CO₂ --, ##STR10## wherein B is CH, CH₂, D is sulfur, and E is CH, CH₂ ; R⁵ and R⁷ are each independently hydrogen or methyl;

q is an integer of from 0 to 1, and

R⁶ is phenyl, substituted phenyl, or cyclohexyl.

Still more preferred compounds of the invention are those of Formula I wherein

R is phenyl

thiophene,

furan,

each unsubstituted, or mono- or disubstituted by alkyl of 1 to 3 carbons, methoxy, ethoxy, chlorine, fluorine, NH₂, or CF₃ ;

R¹ and R² are each independently hydrogen or methyl;

X is ##STR11## R³ is hydrogen or methyl; n is 1;

R⁸ is indole;

Y is ##STR12## R⁵ and R⁷ are each independently hydrogen or methyl; q is 1;

R⁶ is phenyl,

substituted phenyl, or cyclohexyl.

Still more especially preferred compounds of the invention are:

phenylmethyl(S)-[1-(1H-indol-3-ylmethyl)-2-[methyl(phenylmethyl)amino]-2-oxoethyl]carbamate;

phenylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

phenylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

phenylmethyl[S-(R*,R*)]-[1-(1H-indol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]ethyl]methyl]carbamate;

phenylmethyl[S-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]ethyl]methylcarbamate;

(4-chlorophenyl)methyl(S)-[1-(1H-indole-3-ylmethyl)-2-oxo-2-[(phenylmethyl)amino]ethyl]methyl]carbamate;

(4-methoxyphenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

(4-chlorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-ethyl]carbamate;

(4-methylphenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

phenylmethyl(S)-[1-(1H-indol-3-ylmethyl)-2-[methyl(phenylmethyl)amino]-2-oxoethyl]carbamate;

phenylmethyl(S)-[2-[[(4-chlorophenyl)methyl]-amino]1-(1H-indol-3-ylmethyl)-2-oxoethyl]-methylcarbamate;

phenylmethyl(S)-[1-(1H-indol-3-ylmethyl)-2-oxo-2-[[[4-(trifluoromethyl)phenyl]methyl]amino]ethyl]-methylcarbamate;

methyl N-[(phenylmethoxy)carbonyl]-, [3,5-bis(trifluoromethyl)phenyl]-L-tryptophan;

phenylmethyl[1-(1H-indol-3-ylmethyl)-1-methyl-2-[[1-(4-methylphenyl)ethyl]amino]-2-oxoethyl]carbamate;

phenylmethyl[R-(R*,R*)]-[2-[(1-cyclohexylethyl)-amino]-1-(1H-indol-3-ylmethyl)-1-methyl-2-oxoethyl]carbamate;

phenylmethyl[2-[[1-[3,5-bis(trifluoromethyl)-phenyl]ethyl]amino]-1-(1H-indol-3-ylmethyl)-1-methyl-2-oxoethyl]carbamate;

phenylmethyl (R,RS)-[1-(1H-indol-3-ylmethyl)-2-[[1-(4-methoxyphenyl)ethyl]amino]-1-methyl-2-oxoethyl]carbamate;

4-pyridinylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]carbamate;

3-thienylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

2-thienylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

2,3-dihydro-1H-inden-3-yl [R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

1-naphthalenylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

2,3-dihydro-1H-inden-2-yl[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(2-fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

3-furanylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

2-furanylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(3-fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(2,3-difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(4-fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(2,4-difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

(2,5-difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl)amino]ethyl]carbamate;

phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-(1H-indazol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-[(5-fluoro-1H-indol-3-yl)methyl]-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

-phenylmethyl[1-(1-methyl-1H-indol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

phenylmethyl[R-(R*,S*)]-[1-(2-naphthalenyl-methyl)-2-oxo-2-[(1-phenylmethyl)amino]ethyl]carbamate;

1-phenylethyl (S)-N-[(phenylmethoxy)carbonyl)]-DL-tryptophan, (S)-;

phenylmethyl[1-(benzo[b]thien-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate;

carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]-, 2-benzofuranyl-methyl ester, [R-(R*,S*)];

carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]-, benzo[b]thien-2-ylmethyl ester, [R-(R*,S*)];

[2-(1H-indol-3-yl)-1-methyl-1-(1-phenyl-ethylcarbamoyl)-ethyl]-carbamic acid 2-fluoro-5-methyl-benzyl ester;

carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[[1-(4-pyridinyl)ethyl]amino]ethyl]-, 2-benzo-furanylmethyl ester, monohydrochloride, [R-(R*,S*)];

carbamic acid, [1-(1H-indol-3-ylmethyl)-2-[methyl-(phenylmethyl)amino]-2-oxoethyl]-, 2-benzofuranylmethyl ester, (S)-;

carbamic acid, [1-(1H-indol-3-ylmethyl)-2-[methyl-(phenylmethyl)amino]-2-oxoethyl]-, benzo[b]thien-2-ylmethyl ester, (S)-.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat respiratory disorders in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating respiratory disorders in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat inflammation in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating inflammation in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat gastrointestinal disorders in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating gastrointestinal disorders in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat eye diseases such as dry eye and conjunctivitis in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating eye diseases in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat allergies in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating allergies in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat diseases of the central nervous system in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating diseases of the central nervous system in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective to treat migraine in a mammal suffering therefrom, and a pharmaceutically acceptable carrier.

Another aspect of the invention is a method for treating migraine in a mammal such as a human comprising administering a therapeutically effective amount of a compound according to Formula I.

Another aspect of the invention is a pharmaceutical composition comprising an amount of compound according to Formula I effective to treat pain arising from neurogenic inflammation or inflammatory pain.

Another aspect of the invention is a method for treating pain such as pain arising from neurogenic inflammation in inflammatory pain status.

Another aspect of the invention is a pharmaceutical composition comprising an amount of a compound according to Formula I effective in treating conditions associated with aberrant neovascularization: rheumatoid arthritis, atherosclerosis, and tumor cell growth.

Another aspect of the invention is a method of treating conditions associated with aberrant neovascularization: rheumatoid arthritis, atherosclerosis, and tumor cell growth.

Another aspect of the invention is using the compounds as imaging agents for imaging NK₁ receptors in vivo.

Processes for preparing the compounds and novel intermediates are included in the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following terms are descriptive of the compounds of the instant invention.

The alkyl groups contemplated by the invention include straight, branched, or cyclic carbon chains of from 1 to 8 carbon atoms except where specifically stated otherwise. Representative groups are methyl ethyl, propyl, isopropyl, n-propyl, n-butyl, iso-butyl, sec-butyl, 2-methylhexyl, n-pentyl, 1-methylbutyl, 2,2-dimethylbutyl, 2-methylpentyl, 2,2-dimethylpropyl, n-hexyl, and the like.

The cycloalkyl groups contemplated by the invention comprise those having 3 to 6 carbon atoms.

The alkoxy groups contemplated by the invention comprise both straight and branched carbon chains of from 1 to 6 carbon atoms unless otherwise stated. Representative groups are methoxyl, ethoxy, propoxy, i-propoxy, t-butoxy, and hexoxy.

The term halogen is intended to include fluorine, chlorine, bromine, and iodine.

The term aryl is intended to include substituted or unsubstituted phenyl, naphthyl, biphenyl, and indanyl. The substituents include one or more substituents such as halogens, nitro, alkyl, alkoxy, alkylthio, hydroxy, trifluoromethyl, and others as specified or as would occur to one skilled in the art.

The term arylalkyl is as described above for the two terms individually.

The term heterocyclic comprises substituted or unsubstituted pyridyl, 2- or 3-indolyl, thienyl, quinolyl, furanyl, isoquinolyl, benzofuranyl, and benzothiophenyl.

The term amide/ester replacement refers to such moieties as ketomethylene, methyleneoxy, tetrazole, 1,2,4-oxadiazole, and thiazole, etc. See for example Fincham, et al, J Med Chem, 1992;35:1472-1482 or Saunders, et al., J Med Chem, 1990;33:1128-1138.

The compounds of the instant invention are highly selective antagonists of the tachykinin receptor.

One such compound (Ex. 15) is an antagonist of the NK₁ in contrast to substance-P methyl ester which is a known selective NK₁ receptor agonist. See Table I below.

                  TABLE I                                                          ______________________________________                                         NK.sub.1 Antagonist Activity                                                                 pk.sub.B /pA.sub.2                                                             Guinea Pig                                                                               Guinea Pig                                               Example Trachea.sup.a Ileum.sup.b                                            ______________________________________                                         15            7.4       7.8                                                      20 7.0 7.7                                                                     22 7.0 7.8                                                                     45 7.2 8.0                                                                     47 7.3 8.4                                                                     53 8.1 8.6                                                                     54 7.9 8.3                                                                     63 8.7 9.5                                                                     64 7.1 8.7                                                                     67 -- 7.9                                                                    ______________________________________                                          .sup.a Ireland SJ, et al., Regulatory Peptides 1988;22:93.                     .sup.b McKnight AT, et al., Br J Pharmacol 1991;104:35560.               

As can be seen from the data in Table I above, the compounds of the invention (for example, Ex. 15), is a tachykinin NK₁ receptor antagonist in a number of in vitro NK₁ preparations, i.e., it antagonizes the pharmacological action of the selective NK₁ receptor agonist substance-P methylester on these tissues with a pK_(B) of about 8. Therefore, it could be of use in therapeutic disorders where attenuation of the NK₁ receptor response is an appropriate form of intervention.

These compounds are active in vivo as NK₁ receptor antagonists (see Table II). They antagonize the ability of a NK₁ receptor selective agonist (SPOMe) to induce plasma protein extravasation in the guinea pig bladder. The protocol is similar to that described by Eglezos, et al., Eur J Pharmacol 1991;209:277-279.

                  TABLE II                                                         ______________________________________                                         Guinea Pig Plasma Extravasation                                                        Example  ID.sub.50 (mg/kg IV)                                          ______________________________________                                         22           0.64                                                                45 0.61                                                                        47 0.13                                                                        53 0.071                                                                       54 0.051                                                                       63 0.024                                                                       66 2.8                                                                         67 0.91                                                                      ______________________________________                                    

The compounds of the invention were also evaluated in three tachykinin binding assays. For the NK₁ receptor measurement of the binding of [¹²⁵ I-BH]. Substance-P, 0.1 nM to guinea pig cerebral cortex membranes was measured as in Lee C M, et al, Eur J Pharmacol 1986;130:209 and in Br J Pharmacol 1990;99:767.

For the NK₂ receptor measurement of the binding of [¹²⁵ I]-iodohistidyl neurokinin A (0.1 nM) to hamster urinary bladder membrane was measured as described in Buck, Shatzer Life Sci 1988;42:2701.

For the NK₃ receptor measurement of the binding of [³ H]-Senktide (2 nM) to a guinea pig cerebral cortex membrane was taken as described in Lee C M, above.

See Table III below for the binding data for representative compounds of the invention. This table shows in vitro NK₁ receptor binding data for certain compounds of the invention.

                  TABLE III                                                        ______________________________________                                         In Vitro NK.sub.1 Receptor Binding Data                                                          Binding                                                        Example IC.sub.50 (nM)                                                       ______________________________________                                                1      341                                                                3 218                                                                          4 198                                                                          6 75                                                                           7 306                                                                          15 36                                                                          16 702                                                                         20 64                                                                          21 27                                                                          22 17                                                                          23 168                                                                         24 185                                                                         27 306                                                                         29 487                                                                         35 233                                                                         36 70                                                                          37 290                                                                         38 100                                                                         39 10,000                                                                      40 210                                                                         41 >10,000                                                                     42 140                                                                         43 100                                                                         44 110                                                                         45 14                                                                          46 110                                                                         47 10                                                                          48 230                                                                         49 120                                                                         50 120                                                                         51 230                                                                         52 49                                                                          53 39                                                                          54 19                                                                          55 >1000                                                                       56 3200                                                                        57 3400                                                                        58 1700                                                                        60 >1000                                                                       63 9                                                                         ______________________________________                                    

Table II shows the concentration of the compounds of the instant invention which is needed to displace 50% of a specific radioligand ([125I] Bolton Hunter labeled Substance-P) from tachykinin NK₁ receptor sites in guinea pig cerebral cortex membranes. It is a measure of the affinity these compounds have for this receptor.

As can be seen from the binding data above, several of these compounds have high affinity for the NK₁ receptor.

Compounds of the invention are expected to be useful in treating disorders mediated by tachykinins such as respiratory disorders, especially asthma.

They are also expected to be useful in treating inflammation such as arthritis, gastrointestinal disorders such as colitis, Crohn's disease, and irritable bowel syndrome.

They are further expected to be useful in treating and/or preventing eye diseases such as dry eye and conjunctivitis.

They are further expected to be useful in treating allergies such as rhinitis (common cold), and eczema.

The compounds are expected to treat vascular disorders such as angina and migraine.

They are further expected to be useful in preventing and/or treating diseases of the central nervous system such as schizophrenia.

Scheme I below illustrates the synthesis of Examples 1-8 and 35, CBZ-Trp-OPFP (carbobenzoxy-Trp-pentafluorophenyl) was treated with N-methyl benzylamine in EtOAc to give Examples 1-3 when using the appropriate tryptophan stereochemistry (i.e., Example 2 uses R-Trp etc). Examples 4-8 were prepared using the same pentafluorophenyl ester of tryptophan as above but this time it was reacted with RS,R or S α-methylbenzylamine using EtOAc as the solvent. The compound of Example 35 was prepared by reacting the above PFP ester with 3,5 di-CF₃ benzyl alcohol.

                                      SCHEME I                                     __________________________________________________________________________     1  STR13##                                                                     2  STR14##                                                                        -                                                                           Example Number                                                                                                                                                 Example Number                                                                                                                                                  ▪                                     __________________________________________________________________________       1 RS 4 RS RS                                                                   2 R 5 R R                                                                      3 S 6 R S                                                                        7 S S                                                                          8 S R                                                                      __________________________________________________________________________      Reagents: a) PhCH.sub.2 N(Me)H; b) PhCH(Me)NH.sub.2 ; c)                       (3,5diCF.sub.3)PhCH.sub.2 OH                                             

In Scheme II (see below) the versatile intermediate, CBZ-tryptophanyl pentafluorophenyl ester was treated with a variety of arylmethylamines. Example 9 was prepared using 4-chlorobenzylamine in ethyl acetate. Similarly, Example 10 was prepared using 1,2,3,4-tetrahydronaphthyl-1-amine under similar conditions to that for Example 9. Another versatile intermediate shown in Scheme II is the N-terminal unprotected tryptophanyl benzylamide, treatment of this in dry dichloromethane with 1-phenylethanol in the presence of 4-nitrophenylchloroformate yielded Example 11. ##STR15## Reagents: a) ArCH₂ NH₂ ; b) 1,2,3,4-tetrahydronaphthyl-1-amine; c) 1-phenylethanol and nitrophenylchloroformate

Scheme III below outlines the synthesis of Examples 12-18, α-Methyl tryptophan methylester was initially treated with benzylchloroformate in aqueous 1,4-dioxane and in the presence of base to give the CBZ-protected ester. This ester was then saponified with lithium hydroxide to the corresponding acid which was then treated with dicyclohexylcarbodiimide (DCC) in the presence of pentafluorophenol (PFP--OH) to give CBZ-α-methyl tryptophan pentafluorophenyl ester. This active ester was treated with benzylamine to give Example 12. The same ester was also treated with N-methylbenzylamine to yield Example 13. Examples 14-18, 36, 37, 38, 39, and 40 were prepared again from this PFP-ester using the appropriate amine.

                                      SCHEME III                                   __________________________________________________________________________     3  STR16##                                                                     4  STR17##                                                                        -   Example Number                                                                          ▪                                                                        R.sup.1                                      __________________________________________________________________________       12 RS -- --                                                                    13 R -- --                                                                     14 R RS 4ClPh                                                                  15 R S Ph                                                                      16 S S Ph                                                                      17 S R Ph                                                                      18 R R Ph                                                                      36 R R or S 4-CH.sub.3 Ph                                                      37 R R or S 4-CH.sub.3 Ph                                                      38 R S c-Hexyl                                                                 39 R R,S (3,5-diCF.sub.3)Ph                                                    40 R R,S 4-OCH.sub.3 Ph                                                      __________________________________________________________________________      Reagents: a) i. PhCH.sub.2 OCOCl; ii. LiOH; iii. DCC,PfP; b) PhCH.sub.2        NH.sub.2 ; c) PhCH.sub.2 N(Me)H; d) R.sup.1 CH(Me)NH.sub.2               

The synthetic routes described in Scheme IV below involve the very useful intermediate α-methyltryptophanyl-1-phenethylamide which can be synthesized from Example 15 by hydrogenation of the CBZ-N-terminal protecting group using Pearlmans catalyst in ethanol. This free amine may then be reacted with the appropriate chloroformate or active carbonate to give Examples 20-22, 41-54, and 63-65. Example 19 was prepared by the action of the amine on benzyl isocyanate.

                                      SCHEME IV                                    __________________________________________________________________________     5  STR18##                                                                     6  STR19##                                                                        -    Example Number                                                                            ▪                                                                      R.sup.1                                     __________________________________________________________________________       19 R S --                                                                      20 R S 4MeO--PhCH.sub.2                                                        21 R S 4Cl--PhCH.sub.2                                                         22 R S 4CH.sub.3 --PhCH.sub.2                                                  41 S S 4-pyridylCH.sub.2                                                       42 S S 3-thienylCH.sub.2                                                       43 R S 2-thienylCH.sub.2                                                        - 44 R S                                                                                                       7  STR20##                                     - 45 R S 2-Naphthalene CH.sub.2                                                - 46 R S                                                                                                       8  STR21##                                     - 47 R S 2-FPhCH.sub.2                                                        48 R S 3-FuranylCH.sub.2                                                       49 R S 2-FuranylCH.sub.2                                                       50 R S 3-FPhCH.sub.2                                                           51 R S 4-FPhCH.sub.2                                                           52 R S 2,3 diF--PhCH.sub.2                                                     53 R S 2,4 diF--PhCH.sub.2                                                     54 R S 2,5 diF--PhCH.sub.2                                                     63 R S 2-BenzofuranylCH.sub.2                                                  64 R S 2-BenzothiophenylCH.sub.2                                               65 R S (2-F,5-CH.sub.3)--PhCH.sub.2                                          __________________________________________________________________________      from Scheme III                                                                Reagents: a) Pd(OH).sub.2, H.sub.2, EtOH; b) PhCH.sub.2 N═C═O; c)      ArCH.sub.2 OCOX                                                          

As illustrated in Scheme V below, abrine (N-methyl tryptophan) gave benzyloxycarbonyl-abrine when exposed to benzylchloroformate in aqueous 1,4-dioxane in the presence of base. This N-protected abrine was then used to prepare many derivatives having various C-terminal groups. Example 25 was synthesized by preparing an active ester of the abrine derivative with pentafluorophenol and dicyclohexylcarbodiimide then reacting this with N-methylbenzylamine. Similarly, Examples 23, 26, and 28 were prepared by the reaction of this active ester with various aryl amines such as 4-trifluoromethylbenzylamine (Example 26) and 4-chlorobenzylamine (Example 28). Examples 24 and 27 were made by reaction of the same active ester with α-methylbenzylamine (1-phenethylamine).

                                      SCHEME V                                     __________________________________________________________________________     9  STR22##                                                                     0  STR23##                                                                        -   Example Number                                                                            ▪                                                                      Ar                                           __________________________________________________________________________       23 S -- Ph                                                                     24 S S --                                                                      25 S -- --                                                                     26 S -- C.sub.6 H.sub.4 -4CF.sub.3                                             27 S R --                                                                      28 S -- C.sub.6 H.sub.4 -4Cl                                                 __________________________________________________________________________       Reagents: a) PhCH.sub.2 OCOCl; b) i. DCC, PfP; ii. ArCH.sub.2 NH.sub.2 ;      c) i. DCC, PfP; ii. PhCH.sub.2 (Me)NH.sub.2 ; d) i. DCC, PfP; ii.              PhCH.sub.2 N(Me)H                                                        

Methods for derivatizing the N-terminus of the abrine-containing compounds were carried out via the methods shown in Scheme VI below. Abrine was treated with 9-fluorenylmethylchloroformate in aqueous 1,4-dioxane with sodium carbonate to give the FMOC-protected abrine. The active ester of this (PFP-OH,DCC) was then treated with benzylamine in ethyl acetate to give the amide which was deprotected under the standard conditions of 20% piperidine in DMF. This free amine was then treated with 4-chlorobenzyl chloroformate, 4-trifluoromethylbenzylchloroformate, and 2,3 dimethoxybenzyl-4'-nitrophenyl carbonate to give Examples 29, 30, and 31, respectively.

                                      SCHEME VI                                    __________________________________________________________________________     1  STR24##                                                                     2  STR25##                                                                     3  STR26##                                                                        -                                                                           Example Number                                                                       Ar                                                         __________________________________________________________________________       29 S C.sub.6 H.sub.4 -4Cl                                                      30 S C.sub.6 H.sub.4 -4CF.sub.3                                                31 S C.sub.6 H.sub.3 -2,3,diMeO                                              __________________________________________________________________________      Reagents: a) FMOC--Cl; b) i. DCC, PfP; ii. PhCH.sub.2 NH.sub.2 ; c)            piperidine, DMF; d) ArCH.sub.2 OCOX                                      

Examples 32, 33, 34, and 55-59 were prepared according to Scheme VII below. The appropriate amino acids were reacted to give their CBZ-protected derivatives. These compounds were then treated via their active esters with the appropriate amine or alcohol to produce the desired product. ##STR27##

    ______________________________________                                         Example Number                                                                                                                                                      ▪                                                                             Ar       R.sup.1                                  ______________________________________                                         32           R,S    --       (4-C1)Ph H                                          33 R,S -- (4-Br)Ph H                                                           34 R,S -- (3,4-diOH)Ph H                                                       55 R,S S 3-Indazole CH.sub.3                                                   56 R,S S 3-((5-F)Indole) CH.sub.3                                              57 R,S R,S 3(N-Me Indole) CH.sub.3                                             58 R S 2-Naphthalene CH.sub.3                                                  59 R,S S -- --                                                               ______________________________________                                          Reagents:

a) PhCH₂ --OCOX; X is a leaving group

b) i. activation of carboxylic acid; ii. PhCH(R¹)NH₂

c) DCC, PhCH(CH₃)OH

Example 60 was prepared by the method shown in Scheme VIII below. The methyl ester of 3-benzothiophenylalanine was reacted with dibenzyldicarbonate to give the CBZ-protected derivative. This was then treated with base to give the carboxylic acid, which subsequently was activated and reacted with the appropriate amine. ##STR28## Reagents: a) (PhCH₂ OCO)₂ ; b) LiOH; c) i. HOBt, DCC, ii. (S)PhCH(CH₃)NH₂

Example 61 was prepared by the method shown in Scheme IX below. CBZ α-Me tryptophan was activated to give the pentafluorophenyl ester (described in Scheme III) and reacted with the appropriate amino alcohol. This was then cyclized with Lawesson's reagent to give product.

                                      SCHEME IX                                    __________________________________________________________________________     4  STR29##                                                                     5  STR30##                                                                        -                                                                           Example Number R  n                                                                          ▪                                        __________________________________________________________________________       61 CH.sub.3 1 R R                                                            __________________________________________________________________________      Reagents: a) i activation of acid; ii. amino alcohol b) Lawesson's reagen

Example 62 was prepared by the method shown in Scheme X below. The methyl ester of tryptophan was converted to the N-formyl derivative which was subsequently treated with (BOC)₂ O to protect the indole nitrogen. The isonitrile was then formed and alkylated with bromoacetonitrile. The resulting product was treated with hydrochloric acid followed by benzylchloroformate to give the urethane. Next, the BOC-group was removed and the ester hydrolysed with lithium hydroxide. The acid was then activated an subsequently condensed with α-methylbenzylamine. ##STR31##

Example 66 was prepared by the method shown in Scheme XI below. The mixed carbonate was obtained by reduction of the carboxylic acid and reaction with p-nitrophenylchloroformate. This was then treated with the methyl ester of α-methyl tryptophan to yield the urethane; which was hydrolysed with base to give the acid. The resulting product was then activated as its p-nitrophenylester.

4-Acetyl pyridine was converted to the oxime, which was subsequently reduced to give the primary amine. This was reacted with the p-nitrophenyl-ester to give the amide. This was then converted to the hydrochloride salt. ##STR32##

Examples 67 and 68 were prepared by the method shown in Scheme XII below.

The BOC-protected-(S)-tryptophan-N-hydroxy-succinimidyl ester was reacted with N-methyl benzylamide to give the BOC-(s)-tryptophan-N-methyl-benzylamine which was deprotected with TFA to give the unprotected (S)-tryptophanyl-N-methyl benzylamide. This free amine was then reacted with the benzothiophenyl carbonate to give Example 68 and with the benzofuranylcarbonate to give Example 67. ##STR33##

For preparing pharmaceutical compositions from the compounds of this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets, and suppositories.

A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, or tablet disintegrating agents; it can also be an encapsulating material.

In powders, the carrier is a finely divided solid which is in a mixture with the finely divided active component. In tablets, the active component is mixed with the carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired.

For preparing suppository preparations, a low-melting wax such as a mixture of fatty acid glycerides and cocoa butter is first melted and the active ingredient is dispersed therein by, for example, stirring. The molten homogeneous mixture is then poured into convenient sized molds and allowed to cool and solidify.

The powders and tablets preferably contain 5% to about 70% of the active component. Suitable carriers are magnesium carbonate, magnesium stearate, talc, lactose, sugar, pectin, dextrin, starch, tragacanth, methyl cellulose, sodium carboxymethyl cellulose, a low-melting wax, cocoa butter, and the like.

The compounds of the invention include solvates, hydrates, pharmaceutically acceptable salts, and polymorphs (different crystalline lattice descriptors) of the compounds of Formula I.

The compounds of the present invention can have multiple chiral centers in the above Formula I depending on their structures. In particular, the compounds of the present invention may exist as diastereomers, mixtures of diastereomers, or as the mixed or the individual optical enantiomers. The present invention contemplates all such forms of the compounds. The mixtures of diastereomers are typically obtained as a result of the reactions described more fully below. Individual diastereomers may be separated from mixtures of the diastereomers by conventional techniques such as column chromatography or repetitive recrystallizations. Individual enantiomers may be separated by conventional methods well known in the art such as conversion to a salt with an optically active compound, followed by separation by chromatography or recrystallization and reconversion to the nonsalt form.

Where it is appropriate to form a salt, the pharmaceutically acceptable salts are acetate, benzenesulfonate, benzoate, bicarbonate, bitartrate, bromide, calcium acetate, camsylate, carbonate, chloride, citrate, dihydrochloride, edetate, edisylate, estolate, esylate, fumarate, gluceptate, gluconate, glutamate, glycollylarsanilate, hexylresorcinate, hydrabamine, hydrobromide, hydrochloride, hydroxynaphthoate, iodide, isethionate, lactate, lactobionate, malate, maleate, mandelate mesylate, methylbromide, methylnitrate, methylsulfate, mucate, napsylate, nitrate, pamoate (embonate), pantothenate, phosphate/diphosphate, polygalacturonate, salicylate, stearate, subacetate, succinate, sulfate, tannate, tartrate, theoclate, triethiodide, benzathine, chloroprocaine, choline, diethanolamine, ethylenediamine, meglumine, procaine, aluminum, calcium, lithium, magnesium, potassium, sodium, and zinc.

Cyclodextrin is one suitable inclusion in a pharmaceutical preparation.

The term "preparation" is intended to include the formulation of the active component with encapsulating material as a carrier providing a capsule in which the active component (with or without other carriers) is surrounded by a carrier which is thus in association with it. Similarly, cachets are included.

Tablets, powders, cachets, and capsules can be used as solid dosage forms suitable for oral administration.

Liquid form preparations include solutions, suspensions, and emulsions. Sterile water or water-propylene glycol solutions of the active compounds may be mentioned as an example of liquid preparations suitable for parenteral administration. Liquid preparations can also be formulated in solution in aqueous polyethylene glycol solution.

Aqueous solutions for oral administration can be prepared by dissolving the active component in water and adding suitable colorants, flavoring agents, stabilizers, and thickening agents as desired. Aqueous suspensions for oral use can be made by dispersing the finely divided active component in water together with a viscous material such as natural synthetic gums, resins, methyl cellulose, sodium carboxymethyl cellulose, and other suspending agents known to the pharmaceutical formulation art.

Preferably the pharmaceutical preparation is in unit dosage form. In such form, the preparation is divided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of the preparation, for example, packeted tablets, capsules, and powders in vials or ampoules. The unit dosage form can also be a capsule, cachet, or tablet itself, or it can be the appropriate number of any of these packaged forms.

EXAMPLE 1 ##STR34##

N-Methylbenzylamine (0.17 mL, 0.00126 mol) was added to a solution of CBZ-RS-Tryptophan pentafluorophenyl ester (0.64 g, 0.00126 mol) in EtOAc (5 mL) and the residue stirred at room temperature for 2 hours. The solvent was removed in vacuo and the residue dissolved in EtOAc (50 mL) and washed with 2 M hydrochloric acid (2×20 mL), water (2×10 mL), brine (20 mL), dried (MgSO₄) and the solvent evaporated in vacuo. The residue was purified via column chromatography eluting with dichloromethane:methanol (9:1) to give the product as a white solid (0.31 L g, 55%) mp 51-55° C.;

IR (film): 3301 (NH, urethane), 1708 (C=0, urethane), 1636 (C=0, amide), 1496, 1342, and 1232 cm⁻¹ ; NMR (CDCl₃): 2.51 and 2.74 (3H, s, CH₃ N); 3.20 (2H, d, J=7 Hz, Trp-CH₂); 4.0-4.4 (2H, 2×m, ArCH₂ N amide ROT); 4.9-5.1 (3H, m, ArCH₂ O, αCH); 5.83 and 5.89 (1H, d, J=8 Hz, NH carbamate amide ROT); 6.7-7.7 (15H, m, aromatics); 8.2 and 8.3 (1H, s, NH, indole); MS m/e (CI) 442 (M⁺ +1).

EXAMPLE 2 ##STR35##

Method as described for Example 3, Scheme I, but using CBZ-R-Tryptophan pentafluorophenyl ester. Yield (0.08 g, 35%); mp 50-53° C.;

[α]_(D) ²³ -27.2 (C=0.25, MeOH); IR (film): 3296-2928, 1712 (urethane co), 1636 (amide I) and 1525 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.75 (3H, s.CH₃); 3.01 (1H, d.d, J=7.5 and 13.9 Hz, one of Trp βCH₂); 444 (2H, s, CH₂ Ph); 4.54 (1H, m, αCH), 5.01 (2H, s, PhCH₂ O); 6.97-7.37 (15H, m, aromatics); 7.57 (1H, d, J=7.7 Hz, urethane NH); 10.7 (1H, S, indole NH); MS m/e (CI) 442 [M⁺ ].

EXAMPLE 3 ##STR36##

CBZ-L-tryptophan pentafluorophenyl ester (0.50 g, 1 mmol) was prepared in situ and reacted with benzylmethylamine (0.13 mL, 1 mmol) in ethylacetate (5 mL). The reaction mixture was stirred overnight at room temperature then washed with diluent HCl (1×10 mL), water (4×10 mL), and dried over MgSO₄. Removal of the solvent in vacuo resulted in a clear oil which was chromatographed to give the product (0.175 g, 40%); mp 48-50° C.;

[α]_(D) ²³ =+30.4 (c=0.25, MeOH); IR (film): 3305-2927, 1710 (urethane CO), 1635 (amide I) and 1530 cm⁻¹ (amide II); NMR (DMSO-d₆, 1340K): δ 2.50 (3H, 3, CH₃); 3.0: (1H, d.d, J=7.3 and 13.8 Hz, one of βCH₂); 4.43 (2H, s, NCH₂ Ph); 4.72 (1H, m, TrpαCH); 5.00 (2H, S, OCH₂ Ph); 7.02-7.35 (15H, m, aromatics); 7.57 (1H, b, urethane NH); 10.65 (1H, s, indole NH); MS m/e (CI) 442 [M⁺ ].

EXAMPLE 4 ##STR37##

(RS) α-Methylbenzylamine (0.128 mL, 0.001 mol) was added to a solution of (CBZ-RS-tryptophan pentafluorophenyl ester (0.533 g, 0.001 mol) in EtOAc (15 mL) and the mixture stirred at room temperature for 15 min. The solvent was removed in vacuo and the residue dissolved in EtOAc (50 mL) and washed with 2 M hydrochloric acid (2×20 mL), water (2×10 mL), brine (20 mL), dried (MgSO₄) and the solvent evaporated in vacuo. The residue was purified via column chromatography eluting with hexane:ethyl acetate (8:2) to give Example 4 Scheme I as a white solid (0.33 g, 76%) mp 59-62° C.;

NMR: (CD₃ SOCD₃): δ 1.23 and 1.34 (3H, d, J=7 Hz, CHCH₃); 2.8-3.2 (2H, m, IndCH₂); 4.3 (1H, m, CH); 4.9 (3H, m, ArCH₂ O and NHCH); 6.9-7.4 (15H, aromatics and NH carbamate); 7.63 (1H, d, J=8 Hz, 4H-indole); 8.33 and 8.41 (1H, d, J=8 Hz NH amide); 10.8 (1H, s, indole NH); MS m/e (CI) 442 (M⁺ +H).

EXAMPLE 5 ##STR38##

CBZ-DL Tryptophan pentafluorophenyl ester (0.25 g, 0.5 mmol) was prepared in situ, dissolved in ethylacetate (2.5 mL) and (R)-(+)-α-methylbenzylamine (0.06 mL, 0.5 mmol) was added. The reaction mixture was stirred at room temperature until no starting material remained. The white precipitate was collected by filtration and recrystallized from ethylacetate to give Example 5 Scheme I (0.10 g, 44%); mp 169-170° C.;

[α]_(D) ²³ =+12.8° (c=0.5, MeOH); IR (film): 3306, 1705 (urethane co), 1657 (amide I), and 1531 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.35 (3H, d, J=6.7 Hz, CH₃); 2.87 (1H, d.d, J=9.2 and 14.3 Hz, one of Trp βCH₂); 3.06 (1H, d.d, J=4.8 and 14.3 Hz, one of Trp βCH₂); 4.36 (1H, m, CH(CH₃ Ph), 4.90-4.96 (3H, m, CH₂ Ph, αCH); 6.94-7.35 (15H, m, aromatics); 7.63 (1H, d, J=7.8 Hz, urethane NH); 8.41 (1H, d, J=7.8 Hz, amide NH); 10.8 (1H, s, indole NH); MS m/e (CI) 442 [M⁺ ].

EXAMPLE 6 ##STR39##

Method as described for Example 5, Scheme 1, but using (S)-(-)-α-methylbenzylamine. Yield (0.09 g, 21%); mp 160-161° C.;

[α]_(D) ²³ =-26.0 (c=0.5, MeOH); IR (film): 3330, 1709 (urethane co), 1658 (amide I) and 1514 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.23 (3H, d, J=6.8 Hz, CH₃); 2.95 (1H, d.d, J=9.4 and 14.3 Hz, one of Trp βCH₂); 3.08 (1H, d.d, J=5.4 and 14.3 Hz, one of Trp βCH₂); 4.32 (1H, m, CH(CH₃)Ph), 4.86-4.94 (3H, m, PhCH₂, αCH); 6.95-7.34 (15H, m.aromatics); 7.63 (1H, α, J=7.7 Hz, urethane NH); 8.33 (1H, d, J=7.5 Hz, amide NH); 10.8 (1H, s, indole NH); MS m/e (CI) 442 [M⁺ ].

EXAMPLE 7 ##STR40##

Example 5, Scheme I, but using (S)-(-)-α-methylbenzylamine method as described for Example 5, Scheme I. Recrystallization from ethyl acetate gave (0.057 g, 13%); mp 168-170° C.;

[α]_(D) ²³ =-11.6 (c=0.5, MeOH); IR (film): 3294, 1704 (urethane CO), 1656 (amide I) and 1536 cm ⁻¹ (amide II); NMR (DMSO-d₆): δ 1.35 (3H, d, J=6.9 Hz, CH₃); 2.86 (1H, d.d, J=9.2 and 14.3 Hz, one of βCH₂); 3.06 (1H, d.d, 5=4.8 and 14.3 Hz, one of βCH₂); 4.36 (1H , m, CH(CH₃)Ph); 4.90-4.96 (3H, m, PhCH₂, Trp αCH); 6.94-7.35 (15H, m, aromatics); 7.63 (1H, d, J=7.9 Hz, urethane NH); 8.41 (1H, d, J=7.7 Hz, amide NH); 10.8 (1H, s, indole NH); MS m/e (CI) 442 [M⁺ ].

EXAMPLE 8 ##STR41##

CBZ-S-Trp pentafluorophenyl ester (0.50 g, 1 mmol) was prepared in situ, then dissolved in ethyl acetate and (R)-(+)-α-methylbenzylamine (0.13 mL, 1 mmol) was added. The reaction mixture was stirred at rock temperature until no starting material remained. The white precipitate was collected by filtration and purified by chromatography to give the product (0.077 g, 17%); mp 160-163° C.;

[α]_(D) ²³ =+24.4 (c=0.5, MeOH); IR (film): 3307, 1704 (urethane CO), 1657 (amide I) and 1517 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.24 (3H, d, J=7.0 Hz, CH₃); 2.95 (1H, d.d, J=9.4 and 14.3 Hz, one of βCH₂); 3.08 (1H, d.d, J=5.4 and 14.3 Hz, one of βCH₂); 4.32 (1H, m, CH(CH₃)Ph); 4.86-4.94 (3H, m, PhCH₂, Trp αCH); 6.95-7.34 (15H, m, aromatics); 7.63 (1H, d, J=7.7 Hz, urethane NH); 8.32 (1H, d, J=7.8 Hz, amide NH); 10.8 (1H, s, indole NH); MS me (CI) 442 M⁺.

EXAMPLE 9 ##STR42##

Method as described for Example 3, Scheme I, but using 4-chlorobenzylamine. Yield (0.05 g, 11%); mp 177-179° C.;

[α]_(D) ²³ =+10.8 (c=0.5, MeOH); IR (film): 3291, 1704 (urethane CO), 1658 (amide II), and 1535 cm⁻¹ (amide I); NMR (DMSO-d₆): δ 2.95 (1H, d.d, J=9.1 and 14.5 Hz, one of Trp βCH₂); 3.13 (1H, d.d, J=5.3 and 14.5 Hz, one of Trp βCH₂); 4.20-4.36 (3H, m, αCH, NHCH₂); 4.97 (2H, s, PhCH₂ O); 6.94-7.46 (14H, m, aromatics); 7.62 (1H, d, J=7.8 Hz, urethane NH); 8.52 (1H, bt, amide NH); 10.8 (1H, s, indole NH); MS m/e (CI) 462 M⁺.

EXAMPLE 10 ##STR43##

Method as described for Example 3, Scheme I; but using 1,2,3,4-tetrahydro-1-napthylamine. Yield. (0.298 g, 64%); mp 73-76° C.;

IR (film): 3298-2863, 1707 (urethane CO), 1651 (amide I) and 1538 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.52-1.87 (4H, m, CH₂ CH₂); 2.70 (2H, m, CH₂ CH₂ Ph); 2.91-3.16 (2H, m, Trp βCH₂); 4.32 (1H, m, αCH); 4.96 (3H, m, PhCH₂, NHCHPh); 6.74-7.37 (14H, m, aromatics); 7.63 (1H, m, urethane NH); 8.21 (1/2H, d, J=9.4 Hz, amide NH); 8.32 (1/2H, d, J=8.8 Hz, amide NH); 10.81, 10.79 (1H, 2×s, indole NH); MS m/e (CI) 468 [M⁺ ].

EXAMPLE 11 ##STR44##

A solution of (RS) sec-phenethyl alcohol (2 g, 0.0163 mol) and dry pyridine (1.3 mL, 0.0163 mol) in dry dichloromethane (10 mL) was cooled to 0° C. A solution of 4-nitrophenyl chloroformate (3.28 g, 0.0163 mol) in dry dichloromethane (25 mL) was added dropwise over 15 minutes and the resulting solution stirred at room temperature for 15 hours. The solvent was removed in vacuo (the temperature being kept below 30° C.) and ether (50 mL) was added and the precipitate was removed by filtration. The solvent was removed in vacuo below 30° C. to give the crude mixed carbonate, νmax 1765 cm⁻¹ (c=0), which was used without further purification.

R,S-Tryptophan benzylamide (0.5 g, 0.0018 mol) and triethylamine (0.18 mL, 0.0018 mol) were dissolved in dry DMF (5 mL). A solution of the mixed carbonate (0.52 g, 0.0025 mol) in DMF (5 mL) was added dropwise over 5 minutes, there was an immediate yellow coloration upon addition of the mixed carbonate, and the yellow solution was stirred at room temperature for 5 hours. The reaction mixture was poured into water (50 mL) and extracted with EtOAc (3×10 mL). The organic phase was washed with dilute aqueous NaOH (approx. 1 M) until the disappearance of the yellow color (approx. 5×20 mL) and then with saturated aqueous citric acid (5×20 mL), water (10 mL), brine (20 mL), dried (MgSO₄), and the solvent removed. in vacuo. The crude product was purified by column chromatography, eluting with dichloromethane:ethanol (9:1) to give the urethane, Example 11, Scheme II, as a white solid (0.61 g, 77%); mp 128-132° C.; IR (film): 3317 (NH), 1706 (C=0), carbamate), 1659 (C=0, amide), 1497, 1456, 1378, and 1355 cm⁻¹ ; NMR (DMSO-d₆): 1.35 and 1.4 (3H, d, J=7 Hz, CHCH₃); 2.8-3.2 (2H, m, IndCH₂), 4.3 (3H, m, CONHCH₂ Ph, CH); 5.1 (1H, m, PhCHO); 6.9-7.3 (15H, aromatics and carbamate NH); 7.6 (1H, m, 4H-indole); 8.45 (1H, m, amide NH); 10.7 (1H, m, indole NH); Ms m/e (CI): 442 (M⁺ +H).

EXAMPLE 12 ##STR45##

Benzyl chloroformate (0.85 mL, 0.005 mol) was added in one portion to a vigorously stirred suspension of R,S-α-Me-Trp methyl ester (1 g, 0.0043 mol) and potassium carbonate (2 g, 0.015 mol) in dioxane (15 mL) and water (1 mL). The mixture was stirred at room temperature for 2 hours, after which time t.l.c. analysis indicated the consumption of starting material. The solvent was removed in vacuo. The residue was treated with 2 M hydrochloric acid (10 mL), water (40 mL), and extracted with EtOAc (3×20 mL). The organic phase was washed with water (2×20 mL), brine (10 mL), dried (MgSO₄), and the solvent removed in vacuo to give the N-protected amino ester as an off-white solid (1.39 g, 87%) which was used in the next reaction without further purification.

υmax (film): 3345 br (NH), 1718 br (C=0, ester and carbamate) cm⁻¹. δ (CDCl₃): 1.63 (3H, s, α-CH₃); 3.60 (5H, br.m, OCH₃ and CH₂ -Ind); 5.08 (2H, m, ArCH₂ O); 5.5 (1H, br.s, NH urethane); 6.8-7.5 (11H, aromatics); 8.3 (1H, br.s, NH indole).

A mixture of this ester (1.49 g, 0.004 mol) and lithium hydroxide monohydrate (0.84 g, 0.02 mol) in THF (15 mL) and water (5 mL) was stirred vigorously at room temperature for 15 hours. The solution was extracted with EtOAc (3×10 mL) and the organic phase discarded. The aqueous phase was acidified with 2 M hydrochloric acid (approx. 20 mL) and extracted with EtOAc (3×20 mL). The organic phase was washed with water (20 mL), brine (20 mL), dried (MgSO₄), and the solvent removed in vacuo to give the acid (Scheme III) as a light brown oil (1.31 g, 88%) which was used in the next step without further purification.

υmax (film): 3389 (OH), 1770 (C=0, acid), and 1708 (C=0, carbamate) cm⁻¹.

This crude carboxylic acid (1.1 g, 0.003 mol), N,N'-dicyclohexylcarbodiimide (DCC) (0.618 g, 0.003 mol) and pentafluorophenol (PFP) (0.6 g, 0.0033 mol) were dissolved in EtOAc (20 mL) and the reaction mixture stirred at room temperature for 1 hour. The mixture was filtered to remove the white solid and benzylamine (0.35 mL, 0.0033 mol) was added and the mixture stirred for 10 hours at room temperature. The solvent was removed in vacuo and the crude product was purified by column chromatography, eluting with dichloromethane:methanol (8:2), gigging the benzamide, Example 12, Scheme III, as a white solid (0.97 g, 73%); mp 117-119° C.;

IR (film): 3337 (NH), 1709 (C=0, carbamate), 1657 (C=0, amide), 1517, 1456, and 1352 cm⁻¹ ; NMR (DMSO-d₆): 1.37 (3H, s, α-Me); 3.33 (2H, m, Ind-CH₂); 4.28 (2H, d, J=5 Hz, NCH₂ Ph); 5.04 (2H, m, Ph-CH₂ O); 6.9-7.5 (16H, aromatics and carbamate); 8.2 (1H, br.s, amide NH); 10.83 (1H, s, indole NH); MS m/e (CI); 442 (M⁺ +H).

EXAMPLE 13 ##STR46## Step 1

A solution of R-α-methyl tryptophan methylester (37.16 g, 160.0 mmol) in dry THF (800 mL) and triethylamine (19.43 g, 192 mmol) was cooled to 0° C. and treated with benzylchloroformate (30.03, 176 mmol) in dry THF (200 mL) dropwise. This was allowed to warm to room temperature slowly, then the solvent removed in vacuo. The residue was redissolved in EtOAc (500 mL), washed with H₂ O (500 mL), 2N HCl (500 mL), saturated NaHCO₃ solution (500 mL), then H₂ O (500 mL). The organic phase was dried over MgSO₄, filtered, and evaporated to dryness in vacuo. The residue was purified by silica gel chromatography using 60% Et₂ O in n-hexane as eluant to give the product.

[α]_(D) ²⁰ =+31.7° (c=1, MeOH);

Step 2

The CBZ-αMe-R-tryptophan methyl ester (69.15 g, 150 mmol) was dissolved in THF (800 mL), cooled to 0° C., and treated with LiOH (30 g in 250 mL H₂ O). MeOH was added (150 mL) and the mixture stirred for 3 hours. The solvent was removed in vacuo. The residue was diluted with H₂ O (500 mL) and extracted with CF₂ Cl₂ (2×300 mL). The aqueous phase was acidified using 2 M citric acid and extracted with CH₂ Cl₂ (2×500 mL). The organic phase was washed with water, dried (MgSO₄), and filtered and evaporated to dryness to give the crude acid, 57.5 g (2:1 mix acid:ester). This crude material was used in Step 3.

Step 3

The crude carboxylic acid from Step 2 above was redissolved in EtOAc (320 mL) and treated with pentafluorophenol (21 g, 114 mmol), followed by the dropwise addition of a solution of N,N'-dicyclohexylcarbodiimide (23.5 g, 114 mmol) in EtOAc (150 mL). This was stirred 18 hours at room temperature. The reaction mixture was then filtered, and the filtrate evaporated to dryness. The solid residue was redissolved in CH₂ Cl₂ (200 mL) and absorbed onto silica, and purified by chromatography using 50% EtOAc in n-hexane to give the product 49.77 g (64%) from α-methyl-R-tryptophan methylester;

IR (film): 1785, 1709, and 1520 cm⁻¹ ; NMR (CDCl₃): δ 1.72 (3H, s); 3.44 (1H, d, J=14.7 Hz); 3.66 (1H, d, J=14.7 Hz); 5.15 (2H, m,); 5.22 (1H, br.s); 6.97 (1H, d, J=2 Hz); 7.09 (1H, t, J=7.5 Hz); 7.22 (1H, t, J=8.0 Hz, 7.34 (6H, m); 7.58 (1H, d, J=7.9 Hz); 8.11 (1H, br.s). ##STR47##

A solution of CBZ-α-methyl-R-tryptophan pentafluorophenyl ester (250 mg, 0.50 mmol) in EtOAc (50 mL) was treated with N-benzylmethylamine (900 mg, 7.40 mmol) and stirred at room temperature for 18 hours. This mixture was washed with 2N HCl (50 mL), then H₂ O (50 mL). The organic phase was dried (MgSO₄), filtered, and evaporated to give a crude residue which was purified by reverse-phase chromatography using 50% MeOH in H₂ O as eluant to give the product as a white foam (40 mg, 18%); mp 64-68° C. (MeOH/H₂ O);

IR (nujol mull): 1703 and 1620 cm⁻¹ ; NMR (DMSO-d₆): δ 1.30 (3H, s); 2.90 (3H, brs); 3.20 (1H, d, J=14 Hz); 3.50 (1H, d, J=14 Hz); 4.60 (2H, br); 5.00 (2H, br); 6.8-7.6 (16H, m); 10.9 (1H, br.s); MS (CI) m/e 456 (11, M⁺ +H), 335 (30), 304 (48) 263 (4.5), 91 (100); Analysis calculated for C, H, N; C₂₃ H₂₉ N₃ O₃ 0.25CCl₄ : C, 68.68; H, 5.92; N, 8.51. Found: C, 68.68; H, 5.90; N, 8.38.

EXAMPLE 14 ##STR48##

A solution of CBZ-α-methyl-R-tryptophan pentafluorophenyl ester (1000 mg, 1.929 mmol) in EtOAc (50 mL) was treated at room temperature with 4 chloro-α-methylbenzylamine (1100 mg, 7.069 mmol) for 1 hour with stirring. The reaction mixture was then washed with 2N HCl (80 mL), then H₂ O (100 mL). The organic phase was dried over MgSO₄, filtered, and evaporated to dryness in vacuo. The residue was purified by chromatography using 20% Et₂ O in CH₂ Cl₂ as eluant to give the product as a white foam and a 1:1 mixture of diasteroisomers (820 mg, 87%); mp 56-58° C. (Et₂ O/CH₂ Cl₂);

IR (nujol mull): 710 and 1651 cm⁻¹ ; NMR (DMSO-d₆): δ 1.20-1.40 (6H, m); 3.10-3.50 (2H, m); 4.80 (1H, m); 5.00 (2H, s); 6.80-7.50 (14H, m); 7.90 1H, d, J=8 Hz); 8.1 (1H, d, J=8 Hz); 10.80 (1H, s).

EXAMPLE 15 ##STR49##

A solution of CBZ-α-methyl-R-tryptophan pentafluorophenyl ester (730 mg, 1.40 mmol) in EtOAc (15 mL) was treated with S(-)α-methylbenzylamine (940 mg, 7.76 mmol) and left stirring at room temperature for 1 hour. The mixture was washed with 2 M HCl (20 mL) then H₂ O (20 mL). The organic phase was dried over MgSO₄, filtered, and evaporated to dryness in vacuo. The residue was then subject to reverse phase chromatography using 80% MeOH; 20% H₂ O as eluant to give the product as a white foam (150 mg, 24%); mp 107-109° C. (H₂ O/MeOH);

[α]_(D) ²⁰ =+13° (c=0.5, MeOH); IR (film): 3460-3400, 1711, 1658, 1495, and 1251 cm⁻¹ ; NMR (DMSO-d₆): δ 1.32 (3H, d, J=7 Hz); 1.38 (3H, s); 3.20-3.40 (2H, m); 4.90 (1H, m); 5.00 (2H, s); 6.80 (1H, s); 6.90 (1H, t, J=7 Hz); 7.00 (1H, t, J=7 Hz); 7.01-7.40 (12H, m); 7.50 (1H, d, J=8 Hz); 8.00 (1H, d, J=8 Hz); 10.80 (1H, s); MS (CI) 456 (30, M⁺ +H), 130 (100), 91 (57), 105 (33). Analysis calculated for C, H, N, C₂₈ H₂₉ N₃ O₃.0.5H₂ O: C, 72.39; H, 6.51; N, 9.04%. Found: C, 72.53; H, 6.48; N, 8.98%.

EXAMPLE 16 ##STR50##

Method as for Example 15, Scheme III except using CBZ-α-methyl-S-tryptophan pentafluorophenyl ester (142 mg, 23%); mp 107-110° C. (MeOH:H₂ O);

IR (film): 3327, 1716, and 1653 cm⁻¹ ; NMR (DMSO-d₆): δ 1.20-1.40 (6H, m); 3.10-3.40 (2H, m); 4.90 (1H, m); 5.00 (2H, s); 6.80-7.50 (16H, m); 7.90 (1H, d, J=8 Hz); 10.80 (1H, br.s). Analysis calculated for C, H, N, C₂₈ H₂₉ N₃ O₃.0.25H₂ O: C, 73.10; H, 6.46; N, 9.13%. Found: C, 73.40; H, 6.41; N, 9.18%.

EXAMPLE 17 ##STR51##

Method as for Example 15, Scheme III except using CBZ-α-methyl-S-tryptophan pentafluorophenyl ester and R(+)-α-methylbenzylamine (190 mg, 30%); mp 109-111° C. (MeOH/H₂ O);

[α]_(D) ²⁴ =-13.2° (c=0.5, MeOH); IR (film): 1719 and 1654 cm⁻¹ ; NMR (DMSO-d₆): 1.34 (3H, d, J=7.9 Hz); 1.39 (3H, s); 3.28-3.36 (2H, m); 4.92 (1H, m); 5.04 (2H, s); 6.82 (1H, s); 6.87 (1H, br); 6.93 (1H, t, J=7.6 Hz); 7.02 (1H, t, J=7.0 Hz); 7.22-7.47 (11H, m); 7.50 (1H, d, J=7.8 Hz); 8.02 (1H, d, J=8.2 Hz); 10.8 (1H, s); MS (CI) m/e 456 (25, M⁺ +H), 130 (100), 91 (73), 105 (35), 304 (29); Analysis calculated for C, H, N, C₂₈ H₂₉ N₃ O₃.0.25H₂ O: C, 73.10; H, 6.46; N, 9.13%. Found: C, 73.27; H, 6.45; N, 9.22%.

EXAMPLE 18 ##STR52##

Method as for Example 15, Scheme III, except using (R)(+)α-methylbenzylamine (150 mg, 24%); mp 63-68° C. (MeOH/H₂ O);

[α]_(D) ²⁸ =+9.4° (c=0.5, MeOH); IR (film): 17H, 1658 cm⁻¹ ; NMR (DMSO-d₆): δ 1.28 (3H, d, J=6.8 Hz); 1.34 (3H, s); 3.16-3.30 (2H, m); 4.89 (1H, m); 5.04 (2H, s); 6.89 (1H, s); 7.00 (1H, t, J=7.9 Hz); 7.20-7.45 (13H, m); 7.48 (1H, d, J=7.8 Hz); 7.88 (1H, d, J=7.5 Hz); 16.80 (1H, s); MS (CI) m/e 456 (20, M⁺ +H), 130 (100, 191, 150).

EXAMPLE 19 ##STR53##

A solution of Example 15, Scheme III (17 g, 37 mmol) in EtOH (200 mL) was treated with 20% Pd(OH)₂ (1 g, 6% w/w) and put under an atmosphere of hydrogen at 30° C. at a pressure of 45 psi for 3 hours. The reaction mixture was then filtered and evaporated to dryness in vacuo, the residue was purified by SiO₂ chromatography using 0.5% NH₄ OH, 5% MeOH, 94.5% CH₂ Cl₂ as eluant to give the product (8.1 g, 62%);

mp 124.5-125° C.; [α]_(D) ²⁰ =+7.0° (c=1, MeOH); IR (film): 1643, 1512, and 1454 cm⁻¹ ; NMR (CDCl₃): δ 1.42 (3H, d, J=6.9 Hz); 1.46 (3H, s); 1.53 (2H, br.s); 2.81 (1H, d, J=14.2 Hz); 3.46 (1H, d, J=14.2 Hz); 5.02 (1H, dq, J=7 Hz); 6.71 (1H, d, J=2.2 Hz); 7.17 (7H, m); 7.33 (1H, d, J=8.0 Hz); 7.59 (1H, d, J=7.8 Hz); 7.82 (1H, d, J=8 Hz); 8.02 (1H, s); MS (CI) m/e 322 (100, M⁺ +H); Analysis calculated for C, H, N, C₂₀ H₂₃ N₃ O: C, 74.74; H, 7.21; N, 13.07%. Found: C, 74.7; H, 7.25; N, 13.04%.

Step 7 ##STR54##

To a stirred solution of the amine (Scheme IV) (321 mg, 1.0 mmol) in THF (10 mL) was added a solution of benzyl isocyanate (146 mg, 1.1 mmol) in THF (5 mL) dropwise. After 1 hour, the solvent was removed in vacuo and the residue chromatographed using 4% MeOH/CH₂ Cl₂. Crystallization from ether gave product (404 mg, 89%); mp 184-187° C.;

[α]_(D) ²⁰ =27° (c=1, MeOH); IR (film): 3500-3200 (NH), 1646 (broad, CO, urea and amide), 1557, 1455, 1265, 741, and 700 cm⁻¹ ; NMR (CDCl₃): δ 1.28 (3H, d, J 6.9 Hz, CHC₃); 1.48 (3H, s, CCH₃); 3.11 (1H, d, J=14.6 Hz, one of CH₂ indole); 3.41 (1H, d, J=14.6 Hz, one of CH₂ indole); 4.14 (1H, d, J=15.1 and 5.8 Hz, one of CH₂ Ph); 4.24 (1H, dd, H=15.1 and 5.9 Hz, one of CH₂ Ph); 4.82-4.92 (1H, m, CHCH₃); 5.12 (1H, s, CH₂ NHCONH); 5.20-5.30 (1H, m, CH₂ NHCONH); 6.74 (1H, d, J=2.2 Hz, indole, C₂ H); 7.00-7.30 (14H, m, aromatics and CONHCH); 7.51 (1H, d, J=7.7 Hz, indole C₄ -H); 8.22 (1H, s, indole NH); MS m/e (CI⁺): 455 (52) (M⁺ +H), 348 (11), 334 (27), 322 (100), 304 (49), 173 (47), 131 (25), 130 (61), 105 (40), 91 (85); Analysis calculated for C, H, N.

EXAMPLE 20 (Scheme V)

Step 8 ##STR55##

1) To a stirred solution of 4 nitrophenylchloroformate (2.01 g, 10 mmol) in acetone (30 mL), cooled in an ice bath, was added 4-methoxybenzylalcohol (1.38 g, 10 mmol) followed by the dropwise addition of a solution of triethylamine (1.01 g, 10 mmol) in acetone (10 mL). Left to stir overnight, filtered off triethylaminehydrochloride, solvent removed under vacuum. Residue taken up in ethyl acetate (50 mL), washed with citric acid solution (2×30 mL), sodium carbonate solution (5×30 mL), brine (2×30 mL), dried over MgSO₄, and solvent removed in vacuo. Crystallization from ether gave carbonate (2.7 g, 89%);

mp 99-100° C.; IR (film): 1747 (CO, carbonate), 1617, 1519, 1353, 1279, 1255, 1034, 866 cm ⁻¹ ; NMR (CDCl₃): δ 3.83 (3H, s, CH₃₀); 5.24 (2H, s, CH₂ O); ##STR56## 8.23-8.30 (2H, m, ##STR57## ; MS m/e (CI+): 303 (10) (M⁺ +H), 277 (2), 260 (5), 241 (3), 149 (9), 140 (61), 122 (44), 121 (100); Analysis calculated for C, H, N.

2) A solution of carbonate (364 mg, 1.2 mmol), the amine (321 mg, 1.0 mmol), and 4-dimethylamino-pyridine (122 mg, 1.0 mmol) in DMF (20 mL) was stirred overnight before solvent was removed under vacuum. Residue taken up in ethyl acetate (50 mL) and washed with citric acid solution (2×50 mL), brine (30 mL), 2N NaOH solution (5×50 mL), brine (30 mL), dried over MgSO₄, filtered, and solvent removed under vacuum. Residue chromatographed using 2% MeOH/CHCl₂ and crystallization from ether gave product (360 mg, 80%); mp 86-94° C.;

[α]_(D) ¹⁷ =+16.7° (c=1, MeOH); IR (film): 3500-3200 (NH), 1713 (CO, urethane), 1652 (CO, amide), 1614, 1515, 1457, 1246, 1176, 1070, 822, 742, and 701 cm⁻¹ ; NMR (CDCl₃): δ 1.31 (3H, d, J=6.9 Hz, CHCH₃); 1.60 (3H, s, CCH₃); 3.24 and 3.46 (each 1H each d, J=14.7 Hz, each one of CH₂ indole); 3.79 (3H, s, OMe); 4.95-5.05 (3H, m, CH₂ OCONH and CONHCH); 5.27 (1H, s, OCONH); 6.35-6.45 (1H, br.d, CONHCH); 6.75 (1H, s, indole C₂ -H); 6.85 (2H, d, J=8.6 Hz, ortho protons to OMe group); 7.09 (1H, t, J=7.4 Hz, indole C₅ or C₆ -H); 7.15-7.30 (8H, m, CH₂ Ph, indole C₅ or C₆ H, meta protons to OMe group); 7.33 (1H, d, J=8.0 Hz, indole C₇ -H); 7.57 (1H, d, J=7.8 Hz, indole C₄ -H); 7.95 (1H, s, indole NH); Analysis calculated for C, H, N.

EXAMPLE 21 (Scheme IV)

Step 9 ##STR58##

1) Method as for Example 20, Scheme IV, except used 4-chlorobenzyl alcohol (1.42 g, 10 mmol) to give a crystalline carbonate (2.9 g, 94%) from ether;

mp 135-138° C.; IR (film): 1761 (CO, carbonate), 1524, 1492, 1350, 1261, 1215 cm⁻¹ ; NMR (CDCl₃): δ 5.26 (2H, s, CH₂ O); 7.35-7.40 (6H, m, aromatics); 8.25-8.30 (2H, m, ##STR59## MS m/e (CI⁺): 308 (6) (M⁺ +H), 292 (4), 278 (7), 266 (15), 264 (41), 140 (43), 127 (82), 125 (100); Analysis calculated for C, H, N, Cl.

2) Method as for Example 20, Scheme IV , except used 4-chlorobenzyl carbonate (368 mg, 1.2 mmol). Chromatography using 3% MeOH/CH₂ C₂ followed by crystallization from ether gave a crystalline product (434 mg, 89%-); mp 98-100° C.;

[α]_(D) ²⁰ =+12.50 (c=1, MeOH); IR (film): 3450-3200 (NH), 1712 (CO, urethane), 1651 (CO, amide), 1494, 1457, 1251, 1073, 742, and 700 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CHCH₃); 1.63 (3H, s, CCH₃); 3.26 (1H, d, J=14.8 Hz, one of CH₂ indole); 3.45 (1H, d, J=14.8 Hz, one of CH₂ indole); 4.95-5.05 (3H, m, CH₂ O and CHCH₃); 5.43 (1H, s, OCONH); 6.27 (1H, d, J=7.5 Hz); 680 (1H, s, indole, C₂ -H); 7.05-7.30 (11H, m, CHPh, Cl--Ar, indole C₅ and C₆ -H); 7.34 (1H, d, J=8.0 Hz, indole C₇ -H); 7.58 (1H, d, J=7.9 Hz, indole C₄ -H); 8.01 (1H, s, indole NH); Analysis calculated for C, H, N.

EXAMPLE 22 (Scheme (IV)

Step 10 ##STR60##

1) Method as for Example 20, Scheme IV except used α-methylbenzylalcohol (1.22 g, 10 mmol) to give a crystalline carbonate (2.3 g, 80%) for ethyl acetate;

mp 93-95° C.; IR (film): 1750 (CO, carbonate), 1536, 1349, 1268, 1218, 865 cm⁻¹ ; NMR (CDCl₃): δ 2.37 (3H, s, CH₃); 5.26 (2H, s, CH₂ O); 7.15-7.40 (6H, m, aromatics); 8.24-8.30 (2H, m, ##STR61## MS m/e (CI⁺): 288 (6) (M⁺ +H); 244 (41), 239 (12), 198 (49), 140 (36), 122 (25), 106 (51), 105 (100); Analysis calculated for C, H, N.

2) Method as for Example 20, Scheme IV, except used 4-methylbenzylcarbonate (345 mg, 1.2 mmol). Residue chromatographed using 2% MeOH/CH₂ Cl₂ and crystallization from ether gave product (350 mg, 75%);

mp 85-95° C. (Needles); [α]_(D) ²⁴ =+15.5° (c=1, MeOH); IR (film): 3500-3200 (NH, 3059, 3028, 2977, 2930, 1709 (CO, urethane), 1652 (CO, amide), 1494, 1457, 1251, 1071, 742, and 700 cm⁻¹ ; NMR (CDCl₃): δ 1.30 (3H, d, J=6.9 Hz, CHCH₃); 1.61 (3H, s, CCH₃); 2.34 (3H, s, Me-aryl); 3.24 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.8 Hz, one of CH₂ indole); 4.95-5.07 (3H, m, CH₂ O and CHCH₃); 5.31 (1H, s, OCONH); 6.38 (1H, d, J=7.7 Hz, CONHCH); 6.77 (1H, d, J=2.2 Hz, indole C₂ -H); 7.05-7.30 (11H, m, CHPh, pMe-Ph, indole C₅ and C₆ -H); 7.33 (1H, d, J=8.1 Hz, indole C₇ -H); 7.58 (1H, d, J=7.7 Hz, indole C₄ -H); 7.98 (1H, s, indole NH); Analysis calculated for C, H, N.

EXAMPLE 23 ##STR62##

Benzylchloroformate (0.85 mL, 0.005 mol) was added in one portion to a vigorously stirred suspension of S-abrine (1 g, 0.0040 mol), potassium carbonate (1.2 g, 0.009 mol) in dioxane (15 mL) and water (1 mL). The mixture was stirred at room temperature for 1 hour, after which time t.l.c. analysis indicated the consumption of starting material. The solvent was removed in vacuo. The residue was treated with 2 M hydrochloric acid (20 mL), water (40 mL), and extracted with EtOAc (3×30 mL). The organic phase was washed with water (10 mL), brine (2×10 mL), dried (MgSO₄), and the solvent removed in vacuo to give the N-protected amino acid (Scheme V) as a dark straw-colored oil (1.25 g, 77%) which was used in the next reaction without further purification; υmax (film): 3345 br (OH), 1740 shoulder (C=0 acid) and 1684 cm⁻¹ v. broad (C=0, carbamate).

The carboxylic acid (0.85 g, 0.0024 mol), N,N'-dicyclohexylcarbodiimide (DCC) (0.56 g, 0.0024 mol) and pentafluorophenol (PFP) (0.44 g, 0.0027 mol) were dissolved in EtOAc (20 mL) and the reaction mixture stirred at room temperature for 1 hour. The mixture was filtered to remove the white solid. Benzylamine (0.3 mL, 0.0026 mol) was added and the mixture stirred for 10 hours at room temperature. The solvent was removed in vacuo and the crude product was purified by column chromatography, eluting with dichloromethane:methanol (9:1) giving Example 23 as a white solid (0.66 g, 63%); mp 48-54° C.;

IR (film): 3326 (NH), 1695 (shoulder, C=0, carbamate), 1662 (C=0, amide), 1547, 1497, and 1402 cm⁻¹ ; NMR (DMSO-d₆): 2.88 (3H, br.s, NHCH₃); 3.10 (1H, br, m, CH_(a) H_(b) Ind); 3.33 (1H, m, CH_(a) H_(b) Ind); 4.32 (2H, d, J=6 Hz, NHCH₂ Ph); 4.8-5.2 (3H, m, ArCH₂ O and CH); 6.8-7.7 (15H, m, aromatics and carbamate NH); 8.65 (1H, s, br, amide NH); 10.85 (1H, s, indole NH); MS m/e (CI) 442 (M⁺ +H).

EXAMPLE 24 ##STR63##

A solution of CBZ-S-abrine pentafluorophenyl ester (100 mg, 0.20 mmol) in EtOAc (10 mL) was treated with S-(-)-α-methylbenzylamine (470 mg, 4.00 mmol) at room temperature for 10 minutes with stirring. The mixture was then washed with diluent HCl (20 mL) then H₂ O (20 mL). The organic phase was dried over MgSO₄, filtered, and evaporated to dryness in vacuo. The residue was purified by chromatography using 10% Et₂ O:90% CH₂ Cl₂ as eluant to give the product as a white foam (68 mg, 77%); mp 58-60° C. (Et₂ O/CH₂ Cl₂);

IR (nujol mull): 1681 and 1656 cm⁻¹ ; NMR (DMSO-d₆): δ 1.40 (3H, d, J=7 Hz), 2.80 (3H, s); 3.00 (1H, m); 3.20 (1H, m); 4.80-5.10 (4H, m); 6.80-7.70 (15H, m); 8.50 (1H, d, J=9 Hz); 10.80 (1H, br); MS (CI) m/e, 456 (55, M⁺ +H), 290 (100), 91 (55). Analysis calculated for C, H, N, C₂₈ H₂₉ N₃ O₃.0.25H₂ O: C, 73.10; H, 6.46; N, 9.13%. Found: C, 73.34; H, 6.41; N, 9.19%.

EXAMPLE 25 ##STR64##

A solution of CBZ-S-abrine pentafluorophenyl ester (100 mg, 0.20 mmol) in EtOAc (20 mL) was treated with N-methyl benzylamine (470 mg, 3.90 mmol) for 10 minutes at room temperature. The mixture was washed with 2N HCl (20 mL, then H₂ O (20 mL). The organic phase was dried (MgSO₄), filtered, evaporated, and the residue subject to reverse phase chromatography using 60%-70% MeOH in H₂ O to give the product as a white foam (66 mg, 75%); mp 44-45° C. (MeOH/H₂ O);

[α]_(D) ²⁰ =-49° (c=0.1, MeOH); IR (nujol mull): 1683 and 1633 cm⁻¹ ; NMR (DMSO-d₆, 360° K): δ 2.80 (3H, s); 2.90 (3H, s); 3.0-3.4 (2H, m); 4.50 (2H, m); 5.00-5.60 (3H, br, m); 6.90-7.60 (15H, m); 10.60 (1H, br); MS (CI) m/e 456 (42, M⁺ +H), 335, 2.90 (100), 91 (62).

EXAMPLE 26 ##STR65##

A solution of CBZ-S-abrine pentafluorophenyl ester (100 mg, 0.20 mmol) in EtOAc (20 mL) was treated with 4-trifluoromethylbenzylamine (1.23 g, 7.03 mmol) for 10 minutes at room temperature. The organic phase was washed with diluent HCl (25 mL) then H₂ O (25 mL), dried (MgSO₄), filtered, and evaporated to dryness in vacuo. The residue was purified by silica gel chromatography using CH₂ Cl₂ then 20% Et₂ O in CH₂ Cl₂ as eluant to yield the product as a white foam (84 mg, 85%); mp 55-57° C. (Et₂ O/CH₂ Cl₂);

[α]_(D) ²⁰ =-58° (c=0.1, MeOH); IR (nujol mull): 1689 and 1660 cm⁻¹ ; NMR (DMSO-d₆): δ 2.80 (3H, s); 3.10 (1H, m); 3.30 (1H, m); 4.40 (2H, d, J=6 Hz); 4.80-5.10 (3H, br.m); 6.90-7.70 (14H, m); 8.70 (1H, br); 10.90 (1H, br); MS (CI) m/e 510 (50, M⁺ +H), 344 (72), 130 (62), 91 (100). Analysis calculated for C, H, N, C₂₈ H₂₆ N₃ O₃ F₃ : C, 66.00; H, 5.14; N, 8.25%. Found: C, 66.17; H, 5.15; N, 8.24%.

EXAMPLE 27 ##STR66##

A solution of CBZ-S-abrine pentafluorophenyl ester (100 mg, 0.20 mmol) in EtOAc (10 mL) was treated with R-(+)-α-methylbenzylamine (470 mg, 4.00 mmol) at room temperature for 10 minutes with stirring. The mixture was then washed with 2N HCl (20 mL) then H₂ O (20 mL). The organic phase was dried over MgSO₄, filtered, and evaporated in vacuo to give a residue that was purified by chromatography using 10% Et₂ O in CH₂ Cl₂ as eluant to give the product as a white foam (62 mg, 71%);

mp 51-56° C. (Et₂ O/CH₂ Cl₂); [α]_(D) ²⁰ =-40° (c=0.5, MeOH); IR (nujol mull): 1690 and 1653 cm⁻¹ ; NMR (DMSO-d₆): δ 1.30 (3H, d, J=7 Hz); 2.80 (3H, br.s); 3.00-3.30 (2H, m); 4.81-5.10 (4H, br.m); 6.90-7.70 (15H, m); 8.40 (1H, br.d, J=9 Hz); 10.80 (1H, br.s); MS (CI) m/e 456 (33, M⁺ +H); 412 (30), 335 (55), 290 (100), 91 (58). Analysis calculated for C, H, N, C₂₈ H₂₉ N₃ O₃.0.25H₂ O: C, 73.10; H, 6.46; N, 9.13%. Found: C, 73.26; H, 6.32; N, 9.11%.

EXAMPLE 28 ##STR67##

A solution of CBZ-S-abrine pentafluorophenyl ester (100 mg, 0.20 mmol) in EtOAc (30 mL) was treated at room temperature with 4-chlorobenzylamine (600 mg, 4.20 mmol) at room temperature for 10 minutes. The reaction mixture was then washed with 2N HCl (50 mL) then H₂ O (50 mL). The organic phase was dried over MgSO₄, filtered, and evaporated to dryness in vacuo. The residue was purified by chromatography using 10% Et₂ O:CH₂ Cl₂ as eluant to give the product as a white foam (62 mg, 60%); mp 56-58° C. (Et₂ O/CH₂ Cl₂);

[α]_(D) ²⁰ =-65° (c=0.25, MeOH); IR (nujol mull): 1683 and 1659 cm⁻¹ ; NMR (DMSO-d₆, 340° C.): δ 2.80 (3H, s); 3.00-3.40 (2H, m); 4.30 (2H, d, J=6 Hz); 5.00 (3H, br); 6.90-7.60 (14H, m); 8.40 (1H, br); 10.60 (1H, br); MS (CI) m/e 476 (55, M⁺ +H), 432 (45), 335 (51), 310 (75), 130 (65), 91 (100). Analysis calculated for C, H, N, C₂₇ H₂₆ N₃ O₃ Cl: C, 68.13; H, 5.51; N, 8.83%. Found: C, 68.02; H, 5.40; N, 8.76%.

EXAMPLE 29 ##STR68## Step 1

To a stirred solution of S-abrine (4.00 g, 18.3 mmol) and sodium carbonate (4.27 g, 40.3 mmol) in aqueous dioxan (1:2, 60 mL), cooled in an ice bath, was added 9-fluorenylmethyl chloroformate (5.69 g, 22 mmol) dropwise in dioxan (40 mL). Mixture was stirred for 4 hours with cooling, then overnight at room temperature. Dioxin was removed in vacuo before diluting with water (100 mL) to obtain a clear solution. Extracted with ether (3×100 mL), ether discarded, aqueous layer acidified using 2N HCl and extracted with ethyl acetate (3×200 mL). Organic layers combined, washed with brine (2×100 mL), dried over MgSO₄, filtered, and solvent removed in vacuo to obtain product (8 g, 990%) as a white noncrystalline solid; mp 80-85° C.;

[α]_(D) ²⁰ =-67.7° (c=1, MeOH); IR (film): 3500-2400, 1715 (CO, carboxylic acid), 1685 (CO, urethane), 1479, 1452, 1404, 1323, 1266, 1198, 1153, 759, and 740 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 2.77 (3H, s, NCH₃); 3.05-3.20 (1H, m, one of CH₂ indole); 3.30 (1H, d.d, J=15.2 and 5.0 Hz, one of CH₂ indole); 4.00-4.30 (3H, br.m, CHCH₂ OCONH); 4.89 (1H, d.d, J=10.2 and 5.0 Hz, CH₂ CHCO₂ H); 6.90-7.10 (3H, m, aromatics); 7.20-7.55 (8H, m, aromatics); 7.83 (2H, d, J=7.5 Hz, fluorenyl, CH₃); 10.65 (1H, s, indole NH); MS m/e (CI⁺): 441 (2) (M⁺ +H), 245 (2), 219 (14), 207 (9), 188 (5), 179 (100), 130 (17).

Step 2 ##STR69##

To a stirred solution of Fmoc-S-abrine (4.40 g, 10 mmol) in ethyl acetate (100 mL), cooled in an ice bath, was added pentafluorophenol (1.84 g, 10 mmol) followed by solid N,N'-dicyclohexylcarbodiimide (2.06 g, 10 mmol). After 4 hours at 0° C., dicyclohexylurea was filtered off and the residue washed with cold ethyl acetate (10 mL). A solution of benzylamine (1.07 g, 10 mmol) was added to the filtrate dropwise over 10 minutes (reaction complete after 15 minutes by IR). Reaction mixture was washed with citric acid solution (2×20 mL), sodium hydrogen carbonate solution (2×20 mL), brine (1×20 mL), dried over MgSO₄, and solvent removed under vacuum. Residue was chromatographed using 30 then 40% ethyl acetate in hexane to give (4.98 g, 94%) as white noncrystalline solid; mp 74-79° C.;

[α]_(D) ²⁰ =-47° (c=1, MeOH); IR (film): 3317 (NH), 3061, 2950, 1669 (br., CO, amide and urethane), 1526, 1453, 1402, 1318, 1248, 1152, 1102, 741, and 700 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 2.83 (3H, s, NCH₃); 3.06 (1H, d.d, J=15.0 and 9.7 Hz, one of CH₂ indole); 3.33 (1H, d.d, J=15.0 and 5.8 Hz, one of CH₂ indole); 4.00-4.40 (3H, brm, CHCH₂ OCO); 4.30 (2H, d, J=5.9 Hz, NHCH₂ Ph); 4.97 (1H, d.d, J=9.6 and 5.9 Hz, CHCH₂ indole); 6.95 (1H, t, J=7.3 Hz, indole CH); 7.00-7.08 (2H, m, indole CH₂); 7.15-7.40 (10H, m, aromatics); 7.44 (1H, d, J=7.3 Hz); 7.51 (1H, d, J=7.4 Hz); 7.61 (1H, d, J=7.8 Hz); 7.82 (2H, d, J=7.6 Hz, fluorenyl CH₂); 8.20-8.30 (1H, br.m, CONH); 10.65 (1H, s, indole NH); MS m/e (CI⁺): 530 (1) (M⁺ +H), 309 (8), 308 (35), 276 (6), 207 (24), 180 (36), 179 (100), 178 (90).

Step 3 ##STR70##

A solution of Fmoc-S-abrine benzylamide (4.0 g, 7.55 mmol) in 20% piperidine in DMF (20 mL) was stirred at room temperature for 5 minutes before removing the solvent under vacuum. Solid residue was stirred vigorously in pet. ether (100 mL), decanted liquid off, and repeated 5 times before leaving to stir overnight in pet. ether (200 mL). Filtered off crystalline product (2.2 g, 95%); mp 140-142° C.;

[α]_(D) ²⁰ =+29.1° (c=1, MeOH); IR (film): 3306 (NH), 1651 (CO, amide), 1523, 1455, 1340, 1103, 742, and 698 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 1.75 (1H, s, NH); 2.20 (3H, s, NCH₃); 2.85 (1H, d, J=14.2 and 7.2 Hz, one of CH₂ indole); 3.02 (1H, d.d, J=14.2 and 6.3 Hz, one of CH₂ indole); 3.24 (1H, t, J=6.8 Hz, CHCH₂ indole); 4.19 (1H, d.d, J=15.1 and 5.6 Hz, one of CH₂ Ph); 4.30 (1H, d.d, J=15.0 and 5.9 Hz, one of CH₂ Ph); 6.96 (1H, t, J=7.2 Hz, indole C₅ or C₆ H); 7.00-7.30 (7H, m, CH₂ Ph and 2 indole CH₃); 7.34 (1H, d, J=8.0 Hz, indole C₇ -H); 7.54 (1H, d, J=7.8 Hz, indole C₄ -H); 8.25 (1H, t, J=6.0 Hz, CONH); 10.80 (1H, s, indole NH); MS m/e (CI⁺): 308 (100 (M⁺ +H), 277 (21), 276 (12), 178 (34), 177 (64), 173 (80), 132 (22), 131 (46), 130 (30), 91 (25). ##STR71## Step 4

To a stirred solution of 4-chlorobenzylalcohol (214 mg, 1.5 mmol) in ethyl acetate (10 mL) at 0° C. was added solid triphosgene (148 mg, 0.5 mmol) followed by the dropwise addition of pyridine (119 mg, 1.5 mmol) in ethyl acetate (5 mL) over 5 minutes. (After 30 minutes IR peak at 1776 cm⁻¹.) Filtered off pyridine hydrochloride, removed solvent under vacuum, residue taken up in THF (5 mL) and added dropwise to a solution of S-abrine benzylamide (307 mg, 1 mmol) and pyridine (119 mg, 1.5 mmol) in THF (20 mL). Intense yellow color as chloroformate added, followed by the precipitation of pyridine hydrochloride. After 30 minutes removed solvent under vacuum and residue chromatographed using 4% MeOH/CH₂ Cl₂ to give product (270 mg, 56%) as noncrystalline solid; mp 52-55° C.;

[α]_(D) ²⁰ =-64.1 (c=1, MeOH); IR (film): 3316 (NH), 1685 (CO, urethane), 1662 (amide), 1530, 1493, 1455, 1399, 1318, 1142, 1092, 1014, and 742 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 2.85 (3H, s, NCH₃); 3.07 (1H, d.d, J=15.0 and 9.9 Hz, one of CH₂ indole); 3.32 (1H, d.d, J=15.0 and 5.8 Hz, one of CH₂ indole); 4.29 (2H, d, J=5.9 Hz, NHCH₂ Ph); 4.80-5.05 (3H, br.m, CH₂ OCONHCH); 6.94 (1H, t, J=7.4 Hz, indole CH); 7.00-7.30 (11H, m, aromatics); 7.34 (1H, d, J=8.5 Hz, indole C₇ -H); 7.57 (1H, d, J=7.5 Hz, indole C₄ -H); 8.30-8.40 (1H, br.s, CONHCH₂); 10.65 (1H, s, indole NH); MS m/e (CI⁺): 476 (32) (M⁺ +H), 434 (17), 432 (44), 369 (23), 297 (17), 276 (100), 177 (24), 171 (24), 130 (57), 125 (51), 91 (24).

EXAMPLE 30 ##STR72## Step 5

Method as for Step 4, Example 29 using 4-trifluoromethylbenzyl alcohol (264 mg, 1.5 mmol) to give product (388 mg, 76%) as noncrystalline solid;

mp 53-57° C.; [α]_(D) ²⁰ =-63.1° (c=1, MeOH); IR (film): 3307 (NH), 1663 (br, CO, amide and urethane), 1531, 1326, 1124, 1067, 1018, 824, and 742 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 2.88 (3H, s, NCH₃); 3.10 (1H, d.d, J=14.9 and 10.0 Hz, one of CH₂ indole); 3.33 (1H, d.d, J=14.9 and 5.7 Hz, one of CH₂ indole); 4.30 (2H, d, J=5.8 Hz, NHCH₂ Ph); 4.90-5.10 (3H, m, CH₂ OCO and CHCH₂ indole); 6.93 (1H, t, J=7.3 Hz, indole CH); 7.00-7.35 (10H, m, aromatics); 7.50-7.65 (3H, m, indole C₇ -H and ##STR73## ; 8.30-8.40 (1H, br.s, CONH); 10.70 (1H, s, indole NH); MS m/e (CI⁺): 510 (89) (M⁺ +H), 490 (12), 446 (15), 403 (41), 277 (34), 276 (100), 171 (26), 159 (30), 130 (63), 91 (24).

EXAMPLE 31 ##STR74## Step 6

A mixture of 2,3-dimethoxybenzyl-4' nitrophenyl carbonate (400 mg, 1.2 mmol) 4-dimethylaminopyridine (122 mg, 1.0 mmol), and S-abrine benzylamide (307 mg, 1.0 mmol) was stirred in DMF (5 mL) for 3 hours before solvent removed under vacuum. Residue taken up in ethyl acetate (50 mL) and washed with citric acid solution (2×50 mL), brine (30 mL), 2N NaOH solution (5×50 mL), brine (30 mL), dried over MgSO₄, filtered, and solvent removed under vacuum. Residue chromatographed using 40% MeOH/CH₂ Cl to give product (500 mg, 100%) as white noncrystalline solid;

mp 49-54° C.; [α]_(D) ²⁰ =-45.3° (c=1, MeOH); IR (film): 3631, 3521, 3411, 3321, 2936, 2836, 1665 (br, CO, urethane and amide), 1589, 1527, 1484, 1456, 1400, 1186, 1151, 1085, 1009, 743, and 701 cm⁻¹ ; NMR (DMSO-d₆) (340K): δ 2.84 (3H, s, NCH₃); 3.07 (1H, d.d, J=14.9 and 9.7 Hz, one of CH₂ indole); 3.32 (1H, d.d, J=14.9 and 5.9 Hz, one of CH₂ indole); 3.65 (3H, s, OCH₃); 3.79 (3H, s, OMe); 4.29 (2H, d, J=5.9 Hz, NHCH₂ Ph); 4.90-5.05 (3H, m, CH₂ OCONCH); 6.65-6.75 (1H, br.s, one of CH₃ on OMe ring); 6.90-7.10 (5H, m, aromatics); 7.15-7.30 (5H, m, aromatics); 7.33 (1H, d, J=8.1 Hz, indole C₇ -H); 7.57 (1H, d, J=7.8 Hz, indole C₉ -H); 8.25-8.35 (1H, m, CONHCH₂); 10.65 (1H, s, indole NH); Ms m/e (CI⁺): 502 (13) (M⁺ +H), 459 (31), 458 (100), 277 (21), 276 (92), 151 (87), 130 (35).

EXAMPLE 32 ##STR75##

Benzylchloroformate (0.94 g, 5.5 mmol) was added dropwise to a suspension of RS-4-chlorophenylalanine (1.0 g, 5.0 mmol) in 1 M Na₂ CO₃ (20 mL), cooled to 0° C. The reaction mixture was stirred for 5 hours at room temperature, then acidified to pH 1 with concentrated HCl. The white precipitate formed was collected by filtration and recrystallized from ethyl acetate/hexane to give CBZ-RS-4-chlorophenylalanine (0.95 g, 57%);

mp 152-155° C.; IR (film): 3309, 1692 (urethane CO) and 1592 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.83 (1H, d.d, J=10.9 and 13.7 Hz, one of βCH₂); 3.07 (1H, d.d, J=4.3 and 13.7 Hz, one of βCH₂); 4.19 (1H, m, αCH); 4.97 (2H, s, CH₂ Ph); 7.31 (9H, m, aromatics); 7.65 (1H, d, J=8.5 Hz, NH); MS m/e (FAB) 334 [MH]⁺. ##STR76##

CBZ-RS-4-chlorophenylalanine (0.5 g, 1.5 mmol) was dissolved in ethyl acetate (5 mL) and dicyclohexylcarbodiimide (0.31 g, 1.5 mmol) was added. Pentafluorophenol (0.28 g, 1.5 mmol) was added and the reaction was stirred overnight at room temperature. The white precipitate formed was removed by filtration and the filtrate concentrated in vacuo to give the activated amino acid as a white solid which was redissolved in ethyl acetate (10 mL). Benzylamine (0.16 mL, 1.5 mmol) was added and the reaction was stirred at room temperature for 1 hour. The white precipitate was collected by filtration and purified by chromatography, followed by recrystallization from ethyl acetate to give the product (0.38 g, 60%);

mp 157-158° C.; IR (film): 3232, 1698 (urethane CO), 1657 (amide I), and 1553 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.82 (1H, d.d., J=10.3 and 13.4 Hz, one of βCH₂); 3.01 (1H, d.d., J=4.5 and 13.4 Hz, one of βCH₂); 4.29 (3H, m, αCH, NHCH₂ Ph); 4.97 (2H, 9, PhCH₂ O); 7.17-7.36 (14H, m, aromatics); 7.58 (1H, d, J=8.6 Hz, NH); 8.53 (1H, t, J=5.8 Hz, NHCH₂ Ph); MS m/e (CI) 423 M⁺.

EXAMPLE 33 ##STR77##

RS-4-Bromophenylalanine (0.98 g, 4 mmol) was suspended in a 1:1 mixture of dioxan/water (20 mL). NaHCO₃ (0.67 g, 8 mmol) was added followed by a solution of dibenzyldicarbonate (1.37 g, 4.8 mmol) in dioxan (5 mL). The reaction was stirred at room temperature overnight, then diluted with water (20 mL). After washing with ether (2×20 mL), the aqueous layer was acidified to pH 1 with concentrated HCl and then was extracted with ethyl acetate (3×20 mL). The combined organic extracts were washed with water (3×30 mL), dried over MgSO₄, and the solvent was removed in vacuo. The white solid obtained was crystallized from ethyl acetate/hexane to give the product (1.16 g, 77%); mp 161-165° C.;

IR (film): 3310, 1694 (urethane CO), and 1532 cm⁻¹ (amide II); NMR (DMSO-d₆): 2.81 (1H, d.d, J=10.7 and 13.7 Hz, one of βCH₂); 3.06 (1H, d.d, J=4.3 and 13.7 Hz, one of βCH₂); 4.19 (1H, m, αCH); 4.97 (2H, s, CH₂ Ph); 7.31 (9H, m, aromatics); 7.76 (1H, d, J=8.5 Hz, NH); MS m/e (FAB) 378, 380 M⁺. ##STR78##

Method as for Example 32, Scheme VII. Yield (0.43 g, 61%); mp 163-164° C.;

IR (film): 3296, 1698 (urethane CO), 1656 (amide I), and 1548 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.78 (1H, d.d, J=10.1 and 13.5 Hz, one of βCH₂); 2.98 (1H, d.d, J=4.4 and 13.5 Hz, one of βCH₂); 4.27 (3H, m, αCH, NHCH₂ Ph); 4.95 (2H, s, PhCH₂ O); 7.16-7.45 (14H, m, aromatics); 7.55 (1H, d, J=8.6 Hz, NH); 8.51 (1H, t, J=5.6 Hz, NHCH₂ Ph); MS m/e (CI) 467, 469 M⁺.

EXAMPLE 34 ##STR79##

RS-3,4-Dihydroxyphenylalanine (0.99 g, 5 mmol) was suspended in a 1:1 mixture of dioxan water. NaHCO₃ (0.84 g, 10 mmol) was added followed by a solution of dibenzyldicarbonate (1.72 g, 6 mmol) in dioxan (5 mL). The reaction was stirred overnight at room temperature under an atmosphere of nitrogen. The solution was diluted with water (20 mL) and was washed with ether (2×20 mL). The aqueous layer was then acidified to pH 1 with concentrated HCl and was extracted with ethyl acetate (3×30 mL). The combined organic extracts were washed with water (3×30 mL) and then were dried over MgSO₄. The solvent was removed in vacuo and the brown oil obtained was partially purified by chromatography to give a brown oil (1.49 g, 90%). The oil (1.49 g, 4.5 mmol) was dissolved in ethyl acetate (15 mL), dicyclohexylcarbodiimide (0.93 g, 4.5 mmol), and pentafluorophenol (0.83 g, 4.5 mmol) were added and the reaction was stirred overnight at room temperature. The precipitate formed was removed by filtration. Concentration of the filtrate in vacuo resulted in an orange oil (2.24 g) which was redissolved in ethyl acetate (10 mL). Benzylamine (0.49 mL, 4.5 mmol) was added and the reaction was stirred at room temperature under an atmosphere of nitrogen for 2 hours. Removal of the solvents in vacuo gave a brownish solid which was purified by chromatography to give the product (0.29 g, 16%); mp 207-208° C.;

IR 3500-3000: 1703 (urethane CO), 1662 (amide I), 1609 (aromatic) and 1547 cm⁻¹ (amide I); NMR (DMSO-d₆): δ 2.62 (1H, d.d, J=9.0 and 13.5 Hz, one of βCH₂); 2.81 (1H, d.d, J=4.6 and 13.5 Hz, one of βCH₂); 4.18-4.33 (3H, m, αCH, NHCH₂ Ph); 4.97 (2H, s, PhCH₂ O); 6.50 (1H, d, J=7.7 Hz, dihydroxy Phe H₅); 6.60 (1H, d, J=7.7 Hz, dihydroxyPhe H₆); 6.67 (1H, s, dihydroxyPhe H₂); 7.14-7.34 (10H, m, aromatics); 7.40 (1H, d, J=8.2 Hz, NH); 8.42 (1H, b.t, NHCH₂ Ph); 8.66 (2H, s, OH×2); MS m/e (CI) 421 [M⁺ ].

EXAMPLE 35 (Scheme I) Methyl N-[(phenylmethoxy)carbonyl]-, [3,5-bis-(trifluoromethyl)phenyl]-L-tryptophan ##STR80##

Z-Trp-OPFP (0.2 g, 0.4 mmol) in EtOAc (30 mL) was treated with 3,5-bis(trifluoromethyl)benzyl alcohol (0.12 g, 0.5 mmol) and DMAP (0.03 g). This mixture was warmed to reflux for 20 minutes. The reaction mixture was washed with 2 M HCl (2×50 mL), then H₂ O (2×50 mL), dried over MgSO₄, and evaporated to dryness in vacuo. The residue was purified by silica gel chromatography using 30% EtOAc in CH₂ Cl₂ as eluant, then by reverse phase silica chromatography using 90% MeOH in H₂ O as eluant to give the product as a white solid (0.192 g, 85%); mp=134-136° C. (MeOH/H₂ O);

[α]_(D) ²⁰ =-8° (c=0.25, MeOH); IR (film): 3409, 1745, 1715, 1506 cm⁻¹ ; NMR (DMSO-d₆): δ 3.15 (2H, m); 4.38 (1H, m); 4.98 (2H, s); 5.20 (1H, d, J=13.3 Hz); 5.32 (1H, d, J=13.4 Hz); 6.96 (1H, t, J=7.4 Hz); 7.05 (1H, t, J=8.1 Hz); 7.16 (1H, s); 7.30 (6H, m); 7.48 (1H, d, J=8.0 Hz); 7.90 (1H, d, J=7.4 Hz); 7.99 (2H, s), 8.05 (1H, s); 10.82 (1H, br s); MS m/e (CI): 565 (22%), 564 (21%), 521 (31%), 504 (36%), 131 (53%), 130 (100%), 91 (83%); Analysis calculated for C₂₈ H₂₂ N₂ O₄ F₆ : C, 59.58; H, 3.93; N, 4.96%. Found: C, 59.87; H, 4.03; N, 4.98%.

EXAMPLES 36 AND 37 Phenylmethyl[1-(1H-indol-3-ylmethyl)-1-methyl-2-[[1-(4-methylphenyl)ethyl]amino]-2-oxoethyl]carbamate ##STR81## Phenylmethyl[1-(1H-indol-3-ylmethyl)-1-methyl-2-[[1-(4-methylphenyl)ethyl]amino]-2-oxoethyl]carbamate ##STR82## Step 1

4'-Methylacetophenone (93.9 g, 0.70 mol) was treated with EtOH (330 mL), H₂ O (400 mL), hydroxylamine hydrochloride (51.1 g, 0.735 mol), potassium hydroxide (94.7 g (85%), 1.44 mmol) and stirred for 12 hours. Solution poured into 1 L of water and treated with excess solid carbondioxide. Filtration and recrystallization from ether/hexane gave pure product (92 g, 88%); mp 82-84° C.;

IR (film): 3327 (broad), 2925, 1607, 1515, 1456, 1369, 1313, 1304, 1180, 1127, 1012, 927, 821, 749 cm⁻¹ ; NMR (CDCl₃): δ 2.29 and 2.37 [each 3H, each s, CH₃ and Ar--CH₃)]; 7.19 (2H, d, J=8.0 Hz, meta to Me); 7.52 (2H, d, J=8.1 Hz, ortho to Me); 9.27 (1H, s, OH); Analysis calculated for C₉ H₁₁ NO: C, 72.46; H, 7.43; N, 9.39%. Found: C, 72.35; H, 7.46; N, 9.38%.

Step 2

Oxime (29.83 g, 0.2 mol) dissolved in absolute EtOH (200 mL) and 10% palladium on carbon (2 g) added. Shaken for 3 hours under an atmosphere of hydrogen at 50 psi before filtering off catalyst using celite. Solvent removed under reduced pressure and residue taken up in 250 mL of ether and amine extracted into 15% hydrochloric acid (50 mL), aqueous phase basified using 50% NaOH solution and product extracted with ether (2×250 mL). Organic phase dried over K₂ CO₃, ether removed under reduced pressure, and residue distilled to give pure product (24.6 g, 91%); bp 120° C. 10 mm Hg;

NMR (CDCl₃): δ 1.37 (3H, d, J=6.6 Hz, CHCH₃); 1.47 (2H, s, NH₂); 2.33 (3H, s, MeAr); 4.08 (1H, q, J=6.6 Hz, CHCH₃); 7.13 (2H, d, J=7.13 Hz); 7.23 (2H, d, J=7.23 Hz); Analysis calculated for C₉ H₁₃ N.0.05H₂ O: C, 79.42; H, 9.70; N, 10.29%. Found: C, 79.36; H, 9.76; N, 10.26%.

Step 3

To a stirred solution CBZ-(R)-α-methyltryptophan-pentafluorobenzyl ester (0.259 g, 0.5 mmol) in EtOAc (30 mL) was added amine (0.081 g, 0.6 mmol) and left to stir overnight at room temperature. Reaction mixture washed with 10% citric acid solution (3×30 mL), H₂ O (30 mL), saturated NaHCO₃ solution (2×30 mL), brine (2×30 mL), dried over MgSO₄, and solvent removed under reduced pressure. Residue chromatographed using ether as eluant or normal phase silica. Crystallization from ether (2 mL) over 2 days in freezer gave pure Isomer I (CAM 2676) (0.09 g, 38%). The filtrate was taken, solvent removed under reduced pressure, and a foam obtained from dichloromethane to give CAM 2677 (Mainly Isomer II, de >70% by NMR, 80 mg, 34%).

Isomer I

mp 155-158° C.; [α]_(D) ²² =8.1° (c=0.5, MeOH); IR (film): 3328 (br, NH), 2926, 1713 (CO, urethane), 1651 (CO, amide), 1505, 1456, 1249, 1070, 81 cm⁻¹ ; NMR (CDCl₃): δ 1.28 (3H, Cl, CHCH₃, J=6.9 Hz); 1.61 (3H, s, CCH₃); 2.32 (3H, s, CH₃ Ar); 3.26 (1H, d, J=14.8 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.7 Hz, one of CH₂ indole); 4.97 (1H, p, J=7.2 Hz, NHCHCH₃); 5.07 (2H, s, CH₂ Ph); 5.37 (1H, s, OCONH); 6.25-6.35 (1H, br.d, NHCH); 6.80 (1H, s, indole C₂ H); 7.03-7.35 (12H, m, aromatics); 7.58 (1H, d, J=7.7 Hz, indole C₄ -H); 7.95 (1H, s, indole NH); MS m/e (CI⁺): 469 (M⁺, 0.2%), 362 (1%), 340 (1%), 318 (3%), 244 (3%), 130 (16%), 119 (13%), 108 (20%), 91 (100%); Analysis calculated for C₂₉ H₃₁ N₃ O₃.0.2H₂ O: C, 73.61; H, 6.69; N, 8.88%. Found: C, 72.68; H, 6.63; N, 8.82%.

Isomer II

mp 62-65° C.; [α]_(D) ²⁰ =+45° (c=0.5, MeOH); IR (film): 3325 (br, NH₃), 3057, 2976, 2925 (CH str), 1715 (CO, urethane), 1652 (CO, amide), 1506, 1456, 1341, 1250, 1070, 817, 74 cm⁻¹ ; NMR (CDCl₃): δ 1.30 (3H, d, J=6.8 Hz, CH₃ CH); 1.56 (2.55H, s, CH₃ C for major diastereoisomer); 1.60 (0.45H, s, CH₃ C for minor diastereoisomer); 2.31 (3H, s, Ar Me); 3.28 and 3.47 (each 1H, each d, J=14.7 Hz, each one of CH₂ indole); 4.92-5.06 (2H, m, CHCH₃, one of CH₂ O), 5.11 (1H, d, J=12.1 Hz, one of CH₂ O); 5.27 (0.85H, s, OCONH); 5.40 (0.15H, s, OCONH); 6.30-6.40 (1H, br.d, CHNH); 6.79 (1H, s, indole C₂ H); 7.05-7.35 (12H, m, aromatics); 7.57 (1H, d, J=7.9 Hz, indole C₄ H); 8.06 (1H, s, indole NH); MS m/e (CI⁺): 470 (M⁺ +H, 9%), 426 (2%), 352 (2%), 340 (11%), 318 (20%), 244 (12%), 130 (94%), 119 (100%), 91 (88%); Analysis calculated for C₂₉ H₃₁ N₃ O₃.0.2H₂ O: C, 73.61; H, 6.69; N, 8.88%. Found: C, 70.56; H, 6.69; N, 8.88%.

EXAMPLE 38 Phenylmethyl[R-(R*,R*)]-(2-[(1-cyclohexylethyl)-amino]-1-(1H-indol-3-ylmethyl)-1-methyl-2-oxoethyl]carbamate ##STR83##

A solution of Z-α-Me-R-Trp-OPFP ester (0.5 g, 0.1 mmol) in EtOAc (30 mL) was treated with cyclohexyl-1-ethyl amine (R isomer) (0.15 g, 1.2 mmol) and stirred for 2 hours at room temperature. The solvent was evaporated and the residue purified by silica gel chromatography using 0-1% MeOH in CH₂ Cl₂ as eluant then by reverse phase silica gel chromatography using 30% MeOH in H₂ O as eluant to give the product as an amorphous white solid (0.277 g, 62%); mp 51-73° C.;

IR (film): 3318, 1709, 1650, 1516, 1655 cm⁻¹ ; NMR (CDCl₃): δ 0.73-0.98 (2H, m); 0.89 (3H, d, J=6.7 Hz); 1.00-1.30 (4H, m); 1.47-1.87 (5H, m); 1.56 (3H, s); 3.28 (1H, d, J=14.7 Hz); 3.48 (1H, d, J=14.5 Hz); 3.64-3.82 (1H, m); 5.08 (2H, br.s); 5.46 (1H, s); 6.13 (1H, d, J=8.8 Hz); 6.87 (1H, d, J=2.2 Hz); 7.06 (1H, dt, J=1.0 and 7.0 Hz); 7.14 (1H, dt, J=1.0 and 7.0 Hz); 7.30 (5H, m); 7.55 (1H, d, J=7.8 Hz); 8.61 (1H, s); Analysis calculated for C₂₈ H₃₄ N₃ O₃.0.25H₂ O: C, 72.31; H, 7.48; N, 9.08%. Found: C, 72.24; H, 7.58; N, 8.81%.

EXAMPLE 39 Phenylmethyl (R,RS)-[2-[[1-[3,5-bis(trifluoromethyl)-phenyl]ethyl]amino]-1-(1H-indol-3-ylmethyl)-1-methyl-2-oxoethyl]carbamate ##STR84##

A solution of Z-αMe-R-Trp-OPFP ester (0.25 g, 0.50 mmol) in EtOAc (50 mL) was treated with 3,5-bis-(trifluoromethyl)-α-methyl-benzylamine (RS mixture) (0.245 g, 0.950 mmol). The reacting mixture was stirred at room temperature for 1 hour, washed 2 M HCl (2×50 mL) and H₂ O (2×50 mL). The organic phase was dried (MgSO₄), filtered, and evaporated to dryness in vacuo. The residue was purified by silica gel chromatography using a 10-80% gradient of EtOAc in hexane as eluant, then by r ever se phase silica gel chromatography using 80% MeOH in H₂ O as eluant to give the product as a white foam (0.232 g, 81%); mp 69-73° C. (CH₂ Cl₂);

[α]_(D) ²⁰ =+29 (c=0.25, MeOH); IR (film): 3327, 1716, 1661, 1506, 1279 cm⁻¹ ; NMR (DMSO-d₆) (340 K): δ 1.25-1.45 (6H, m); 3.20 (1H) and 3.36 (1H) both obscured by H₂ O; 5.04 (3H, mn); 6.79 (1H, br.s); 6.87-7.10 (3H, m); 7.33 (6H, m); 7.46 (1H, d, J=7.8 Hz); 7.87-8.15 (4H, m); 10.70 (1H, br.s); Analysis calculated for C₃₀ H₂₇ N₃ O₃ F₆ : C, 60.91; H, 4.60; N, 7.10%. Found: C, 60.93; H, 4.68; N, 6.96%.

EXAMPLE 40 Phenylmethyl (R,RS)-[1-(1H-indol-3-ylmethyl)-2-[[1-(4-methoxyphenyl)ethyl]amino]-1-methyl-2-oxoethyl]carbamate ##STR85##

Z-R-α-Me-Trp-OPFP ester (0.2 g, 0.4 mmol) in EtOAc (30 mL) was treated with racemic 4-methoxy-α-methylbenzylamine (0.15 g, 1.00 mmol) as the mixture stirred at room temperature for 20 minutes. Triethylamine (1 g, 9 mmol) was then added and the solution stirred a further 30 minutes. The reaction mixture was washed with 1 M HCl (2×50 mL) then H₂ O (2×50 mL), dried (MgSO₄), filtered, and evaporated to dryness in vacuo. The residue was separated by chromatography over silica gel using CH₂ Cl₂ then 20% Et₂ O in CH₂ Cl₂ as eluant to give the product as a white foam (0.176 g, 94%);

mp 62-65° C. (MeOH); [α]_(D) ²⁰ =+19° (c=0.5, MeOH); IR (film): 3338, 2933, 1716, 1652, 1513, 1456, 1247 cm⁻¹ ; NMR (DMSO-d₆): δ 1.26 (1.5H, d, J=7.1 Hz); 1.30 (1.5H, d, J=7.1 Hz); 1.33 (1.5H, s); 1.38 (1.5H, s); 3.30 (2H, obscured by H₂ O); 3.72 (1.5H, s); 3.73 (1.5H, s); 4.85 (1H, m); 5.04 (2H, s); 6.79-6.95 (5H, m); 7.02 (1H, t, J=7.1 Hz); 7.20 (2H, dd, J=8.7 and 12.6 Hz); 7.34 (6H, m); 7.47 (1H, t, J=7.2 Hz); 7.81 (0.5H, d, J=8.0 Hz); 7.93 (0.5H, d, J=8.0 Hz); 10.80 (1H, br.s); MS m/e (FAB): 486 (75%), 356 (100%), 264 (98%); Analysis calculated for C₂₉ H₃₁ N₃ O₄.0.25H₂ O: C, 71.07; H, 6.48; N, 8.57%. Found: C, 71.08; H, 6.58; N, 8.40%.

EXAMPLE 41 4-Pyridinylmethyl[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]carbamate ##STR86## (Veber, et al., J Org Chem 1977;42:3256) (302 mg, 1.1 mmol) and α-methyltryptophanyl-1-phenethylamide (321 mg, 1 mmol) in DMF (10 mL, anhydrous) was added solid DMAP (122 mg, 1 mmol). After stirring overnight at room temperature, the DMF was removed at 60° C. under reduced pressure and the residue suspended between EtOAc (50 mL) and 1N NaOH solution (50 mL). The organic phase was washed with 5×30 mL portions of 1N NaOH solution, brine (30 mL), dried over MgSO₄, filtered, and solvent removed under reduced pressure. Residue chromatographed using normal phase silica with EtOAc/MeOH/NH₃ (90:10:1) to obtain desired product which crystallized from ether giving white needles (180 g, 39%); mp 146-148° C.;

[α]_(D) ²⁰ =+4° (c=0.5, MeOH); IR (film): 3309 (br, NH), 1721 (CDCl urethane), 1650 (CO, amide), 1609, 1494, 1455, 1417, 1342, 1252, 1077, 910, 735, 700, 666 cm⁻ ; NMR (CDCl₃): δ 1.27 (3H, d, J=6.9 Hz, CH, CH₃); 1.67 (3H, s, CCH₃); 3.32 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.47 (1H, d, J=14.7 Hz, one of CH₂ indole); 5.00 (1H, p, J=7.0 Hz, CH₃ CHNH); 5.07 (2H, s, CH₂ O); 6.20 (1H, d, J=7.3 Hz CONHCH); 5.67 (1H, s, OCONH); 6.87 (1H, d, J=2.3 Hz, indole C₂ H); 7.05-7.30 (9H, m, CHPh, 2 indole CH's and 2 pyridyl CH's); 7.36 (1H, d, J=3.0 Hz, indole C₇ H); 7.59 (1H, d, J=7.9 Hz indole C₄ H); 8.09 (1H, s, indole NH); 8.54 (2H, d.d, J=4.4 and 1.6 Hz, pyridyl CH's); MS m/e (CI⁺): 457 (M⁺ +H, 2%), 348 (5%), 244 (4%), 219 (1%), 201 (3%), 138 (10%), 130 (24%), 110 (100%), 92 (52%); Analysis calculated for C₂₇ H₂₈ N₄ O₃.0.25H₂ O: C, 70.34; H, 6.23; N, 12.15%. Found: C, 70.31; H, 6.08; N, 11.99%.

EXAMPLE 42 3-Thienylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR87## Step 1

To a stirred solution of 3-thiophenmethanol (1.14 g, 10 mmol) and 4-nitrophenylchloroformate (2.01 g, 10 mmol) in dichloromethane (50 mL) at. 0° C. was added dropwise a solution of pyridine (0.79 g, 10 mmol) in dichloromethane (10 mL). Reaction mixture allowed to warm to room temperature overnight. Solvent removed under reduced pressure and residue taken up between EtOAc (50 mL) and 10% citric acid solution (50 mL). Organic phase washed successively with 10% citric acid solution (2×30 mL), H₂ O (30 mL), saturated NaHCO₃ solution (2×50 mL), and brine (50 mL). Organic phase dried over MgSO₄, filtered, and solvent removed under reduced pressure. Two crystallizations from EtOAc gave pure product (1.11 g, 40%); mp 75.0-78.4° C.;

IR (film): 1763 (C=0), 1593 (aromatic C--H), 1522 (NO₂), 1491, 1347 (NO₂), 1211, 1164, 862 cm⁻¹ ; NMR (CDCl₃): δ 5.30 (2H, s, CH₂); 7.16-7.18 (1, m, aromatic C-H); 7.35-7.45 (2H, m, aromatic); 7.37 (2H, d, J=9.1 Hz, ##STR88## ; 8.27 (2H, d, J=9.2 Hz ##STR89## Analysis calculated for C₁₂ H₉ NO₅ S: C, 51.61; H, 3.25; N, 5.02; S, 11.48%. Found: C, 51.57; H, 3.21; N, 5.03; S, 11.34%.

Step 2

To a stirred solution of the carbonate (154 mg, 0.55 mmol) and α-methyltryptophanyl-1-phenethylamide (160 mg, 0.5 mmol) in DMF (5 mL, anhydrous) was added solid DMAP (61 mg, 0.5 mmol) and left to stir overnight at room temperature. Solvent removed at 60° C. under reduced pressure and the residue taken up in EtOAc (30 mL) and washed successively with 10% citric acid solution (2×30 mL), H₂ O (30 mL), 1N NaOH (5×30 mL, until aqueous phase no longer intense yellow in color), and brine (2×30 mL). Organic phase dried over MgSO₄, filtered, solvent removed under reduced pressure, and residue crystallized from ether to give pure product (197 mg, 85%); mp 117-121° C.;

IR (film): 3327 (br, NH), 1711 (CO, urethane), 1651 (CO, amide), 1494, 1454, 1247, 1071, 909, 741 cm⁻¹ ; NMR (CDCl₃): δ 1.32 (3H, d, J=6.9 Hz, CH₃ CH); 1.61 (3H, s, CH₃ C), 3.25 (1H, d, J=14.8 Hz, one of CH₂ indole); 3.46 (1H, d, J=15 Hz, one of CH₂ indole); 4.95-5.15 (3H, m, CH₂ O and CHPh); 5.33 (1H, s, OCONH); 6.35-6.45 (1H, br.d, CONHCH); 6.76 (1H, s, indole C₂ H); 7.05-7.35 (11H, m, aromatics); 7.57 (1H, d, J=7.7 Hz, indole C₄ -H); 8.01 (1H, s, indole NH); MS m/e (Cl⁻): 462 (M⁺ +H, 0.2%), 348 (4%), 304 (2%), 244 (5%), 219 (1%), 158 (1%), 130 (37%), 114 (94%), 97 (100%), 85 (71%); Analysis calculated for C₂₆ H₂₇ N₃ O₃ S: C, 67.66; H, 5.90; N, 9.10; O, 6.95%. Found: C, 67,51; H, 5.88; N, 9.03; O, 6.94%.

EXAMPLE 43 2-Thienylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR90## Step 1

See Method as for Example 42. Yield=2.09 g, 75%;

mp 67.5-68.5° C.; IR (film): 1766 (CO, carbonate), 1616 and 1594 (aromatic CH); 1523 (NO₂); 1493; 1347 (NO₂); 1248, 1213, 863 cm⁻¹ ; NMR (CDCl₃): δ 5.45 (2H, s, CH₂ O; 6.98-7.07 (1H, m, aromatic CH); 7.18-7.25 (1H, m, aromatic CH); 7.30-7.43 (1H, m, aromatic CH); 7.38 (2H, d, J=9.2 Hz, CH meta to NO₂); 8.28 (2H, d, J=9.2 Hz, CH ortho to NO₂); Analysis calculated for C₁₂ H₉ NO₅ S: C, 51.61; H, 3.25; N, 5.02%. Found: C, 51.56; H, 3.20; N, 4.94%.

Step 2

See Method as for Example 42. Product chromatographed on normal phase silica using 2% MeOH in CH₂ Cl₂ followed by crystallization from ether gave pure product (220 mg, 95%); mp 125-127° C.;

[α]_(D) ²⁰ =+5.7° (c=0.5, MeOH); IR (film): 3327 (br, NH), 1713, 1651, 1494, 1456, 1247, 1068, 740, 699 cm⁻¹ ; NMR (CDCl₃): δ 1.32 (3H, d, J=6.9 Hz, CH₃ CH),; 1.62 (3H, s, CCH₃); 3.24 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.51 (1H, d, J=14.8 Hz, one of CH₂ indole); 5.01 (1H, p, J=7.1 Hz, NHCHCH₃); 5.19 (1H, d J=12.8 Hz, one of CH₂ O); 5.25 (1H, d, J=12.8 Hz, one of CH₂ O); 5.33 (1H, S, OCONH); 6.30-6.40 (1H, br.d, CONHCH); 6.77 (1H, s, indole C₂ H); 6.93-7.30 (10H, m, aromatics); 7.33 (1H, d, J=8.0 Hz, indole C₇ -H); 7.57 (1H, d, J=7.8 Hz, indole C₄ -H); 7.95 (1H, s, indole NH); MS m/e (CI⁺): 462 (M⁺ +H, 0.2*), 461 (M⁺, 0.2%), 418 (2%), 348 (3%), 304 (3%), 244 (4%), 191 (2%), 130 (30%), 114 (34%), 97 (100%), 85 (47%); Analysis calculated for C₂₆ H₂₇ N₃ O₃ S: C, 67.66; H, 5.90; N, 9.10; S, 6.95%. Found: C, 67.38; H, 5.82; N, 9.02; S, 7.08%.

EXAMPLE 44 2,3-Dihydro-1H-inden-3-yl [R-(R*,S*)]-[1(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(phenylethyl) amino]ethyl]carbamate ##STR91## Step 1

See Method for Example 42. Product unstable on standing and unable to obtain a pure crystalline sample. A sample about 90% by NMR was used as soon as possible for Step 2.

Step 2

See Method for Example 42. Crude product chromatographed using normal phase silica using 1.5% MeOH in CH₂ Cl₂ then rechromatographed using 35% EtOAc in hexane to give pure product (1:1 mix of diastereoisomers, 30 mg, 12%); mp 75-80° C.;

[α]_(D) ²⁰ =+13.8° (c=0.5, MeOH); IR (film): 3331 (br, NH), 3057, 2976, 2935, 1705 (CO, urethane), 1653 (CO, amide), 1494, 1458, 1376, 1341, 1248, 1070, 742, 700 cm⁻¹ ; NMR (CDCl₃) mix of 2 diastereoisomers: δ 1.31 (1.5H, CH₃ CH of one diastereoisomer, d, J=6.9 Hz); 1.39 (1.5H, d, J=6.9 Hz, CH₃ CH of one diastereoisomer); 1.61 and 1.62 (each 1.5H, each s, CH₃ C for both diastereoisomers); 2.00-2.10 (1H, m, CH of indane); 2.40-2.55 (1H, m, CH of indare); 2.80-2.90 (1H, m, CH of indole); 3.00-3.15 (1H, m, CH of indole); 3.22 (0.5H, d, J=14.7 Hz, one of CH₂ indole for one diastereoisomer); 3.27 (0.5H, d, J=14.6 Hz, one of CH₂ indole for one diastereoisomer); 3.47 (0.5H, d, J=14.1 Hz, one of CH₂ indole for one diastereoisomer); 3.49 (0.5H, d, J=14.0 Hz, one of CH₂ indole for one diastereoisomer); 4.98-5.12 (1H, m, CHCH₃); 5.20 (1H, s, OCONH); 6.10-6.15 (1H, m, CHOCO); 6.40-6.50 (1H, m, CONHCH); 6.80 and 6.84 (each 0.5H, each s, each half of C₂ -H, indole); 7.05-7.43 (12H, m, aromatics); 7.59 (1H, d, J=8.0 Hz, indole C₇ -H); 7.96 and 8.00 (each 0.5H, each s, each half of indole NH); MS m/e (FAB): 5043 (M⁺ +Na, 20%), 482.3 (M⁺ +H, 12%), 4383 (4%), 366.2 (55%), 322.2 (100%), 304.2 (36%); Analysis calculated for C₃₀ H₃₁ N₃ O₃ : C, 74.82; H, 6.49; N, 8.73%. Found: C, 74.62; H, 6.46; N, 8.66%.

EXAMPLE 45 1-Naphthalenylmethyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR92## Step 1

See Method for Example 42. Crystallization of product from crude residue using EtOAc followed by washing with 10% citric acid solution (2×30 mL) and multiple water washes gave pure product (2.37 g, 73%);

mp 150.5-152.5° C.; IR (film): 1752 (C=0), 1615, 1595 (aromatic C-H); 1536 (NO₂); 1360 (NO₂); 1281 cm⁻¹ ; NMR (DMSO-d₆): δ 5.48 (2H, s, Ar CH₂ O; 7.50-7.65 (3H, m, aromatics CH); 7.59 (2H, d, J=9.2 Hz, meta to NO₂ group); 7.90-8.05 (4H, m, aromatic CH); 8.32 (2H, d, J=9.1 Hz, ortho to NO₂ group); Analysis calculated for C₁₈ H₁₃ NO₅ : C, 66.87; H, 4.05; N, 4.33%. Found: C, 66.74; H, 4.06; N, 4.27%.

Step 2

See Method for Example 45. Crude product chromatographed on normal phase silica using 3% MeOH/CH₂ Cl₂ then crystallized from ether to give pure product (220 mg, 87%); mp 121-122° C.;

[α]_(D) ²⁰ =+21.2° (c=0.5, MeOH); IR (film): 3342 (br), 3052, 2924 and 2926 (CH, str); 1717 (CO, urethane); 1653 (CO, amide); 1495, 1457, 1250, 1073, 819, 742 cm⁻¹ ; NMR (CDCl₃): δ 1.28 (3H, d, J=6.9 Hz, CH₃ CH,); 1.63 (3H, s, CH₃ C); 3.26 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.48 (1H, d, J=14.7 Hz, one of CH₂ indole); 5.00 (1H, p, J=7.0 Hz, NHCHCH₃); 5.24 (1H, d, J=12.5 Hz, one of CH₂ O); 5.26 (1H, d, J=12.1 Hz, one of CH₂ O); 5.40 (1H, s, OCONH); 6.30-6.40 (1H, br.d, CONHCH); 6.74 (1H, s, indole C2-H); 7.05-7.30 (7H, m, aromatics); 7.31 (1H, d, J=8.0 Hz, indole C7-H)); 7.40-7.52 (3H, m, aromatics); 7.58 (1H, d, J=8.4 Hz, indole C4-H)); 7.75-7.85 (5H, m, aromatics and indole NH); MS m/e (FAB): 506.3 (M⁺ +H, 100%), 462.3 (5%), 429.1 (15%), 401.0 (14%), 376.2 (18%) 341.4 (50%), 304.2 (54%), 281.1 (34%), 257.3 (34%); Analysis calculated for C₃₂ H₃₁ N₃ O₃ : C, 76.02; H, 6.18; N, 8.31%. Found: C, 75.88; H, 6.19; N, 8.28%.

EXAMPLE 46 2,3-Dihydro-1H-inden-2-yl[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl) amino]ethyl]carbamate ##STR93## Step 1

See Method for Example 42. Product crystallized from EtOAc and washed with ether to give product (1.8 g, 60%); mp 110.5-113.5° C.;

IR (film): 1765 (CO), 1616, 1594 (aromatic C--H); 1525, 1349 (NO₂); 1261; 1226; 1187; 858 cm⁻¹ ; NMR (DMSO-d₆): δ 3.21 (2H, d.d, J=17 and 2.8 Hz CH_(A) H_(B) CHCH_(A) H_(B) ; 3.41 (2H, d.d, J=17 and 6.1 Hz, CH_(A) H_(B) CHCH_(A) H_(B)); 5.51-5.62 (1H, m, CHOCOO); 7.18-7.32 (4H, m, aromatic H); 7.37 (2H, d, J=9.2 Hz, H's meta to NO₂ group); 8.27 (2H, d, J=9.2 Hz, H's ortho to NO₂ group); Analysis calculated for C₁₆ H₁₃ NO₅ : C, 64.21; H, 4.38; N, 4.68%. Found: C, 64.36; H, 4.38; N, 4.68%.

Step 2

See Method for Example 42. Used 180 mg (0.6 mmol) of carbonate. Crude product chromatographed using normal phase silica using 2% MeOH/CH₂ Cl₂ then crystallized from ether to give product (170 mg, 71%);

mp 152-157° C.; [α]_(D) ²² =+15.3° (c=1, MeOH); IR (film): 3326 (br, NH str), 2924 and 2852 (CH, str), 1705 (CO urethane), 1652 (CO, amide), 1494, 1457, 1252, 1073, 819, 741 cm⁻¹ ; NMR (CDCl₃): δ 1.35 (3H, d, J=6.9 Hz, CH₃ CH); 1.58 (3H, s, CCH₃); 2.90-2.98 (2H, m, indane CH); 3.20-3.32 (3H, m, 2 indane CH and one of CH₂ indole); 3.46 (1H, d, J=14.5 Hz, one of CH₂ indole); 5.02 (1H, p, J=6.9 Hz, NHCHCH₃); 5.20 (1H, s, OCONH); 5.38-5.48 (1H, m, CHOCONH); 6.30-6.40 (1H, br.d, CONHCH); 6.87 (1H, s, indole, C₂ H); 7.10-7.35 (12H, m, aromatic CH₃); 7.59 (1H, d, J=8.1 Hz, indole C₄ -H); 8.00 (1H, s, indole NH); m/e (CI+): 482 (M⁺ +H, 6%), 348 (14%), 304 (11), 244 (12%), 145 (14%) 134 (78%), 130 (72%), 117 (100%), 105 (88%), 91 (24%); Analysis calculated for C₃₀ H₃₁ N₃ O₃ : C, 74.82; H, 6.49; N, 8.73%. Found: C, 74.72; H, 6.50; N, 8.76%.

EXAMPLE 47 (2-Fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-[1-phenylethyl)amino]ethyl]carbamate ##STR94## Step 1

See Method for Example 42. Crude residue chromatographed using 10% EtOAc in hexane on normal phase silica then crystallized from ethyl acetate to give pure product (0.990 g, 34%); mp 84-84.5° C.;

IR (film): 1752 (CO, carbonate), 1526 (NO₂), 758 cm⁻¹ ; NMR (CDCl₃): δ 5.38 (2H, s, PhCH₂); 7.08-7.23 (2H, m, aromatic CH); 7.32-7.54 (2H, m, aromatic CH); 7.39 (2H, d, J=9.2 Hz, CH meta to NO₂); 8.27 (2H, d, J=9.2 Hz, CH's ortho to NO₂); Analysis calculated for C₁₄ H₁₀ NO₅ F: C, 57.73; H, 3.46; N, 4.81%. Found: C, 57.77; H, 3.52; N, 4.81%.

Step 2

See Method for Example 42 except used 174 mg (0.6 mmol) of carbonate. Crude product chromatographed on normal phase silica using 2% MeOH/CH₂ Cl₂ then crystallized from ether to give pure product (96 mg, 41%); mp 107-111° C.;

[α]_(D) ²² =+8° (c=0.25, MeOH); IR (film): 3338 (br, NH), 1713 (CO, urethane); 1652 (CO, amide), 1494, 1456, 1341, 1233, 1111, 1071, 909, 743 cm⁻¹ ; NMR (CDCl₃): δ 1.30 (3H, d, J=6.9 Hz, CH₃ CH); 1.62 (2H, s, CH₃ C); 3.26 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.47 (1H, d, J=14.9 Hz, one of CH₂ indole); 5.01 (1H, p, J=7.1 Hz, NHCHCH₃); 5.13 (1H, d, J=12.5 Hz, one of CH₂ O); 5.19 (1H, d, J=12.8 Hz, one of CH₂ O); 5.38 (1H, s, OCONH); 6.35 (1H, d, J=7.6 Hz, NHCH); 6.81 (1H, d, J=2.2 Hz, indole C₂ H); 7.00-7.38 (12H, m, aromatics); 7.58 (1H, d, J=7.8 Hz, indole C₄ -H); 8.00 (1H, s, indole NH); MS m/e (CI⁺): 474 (M⁺ +H, 5%), 348 (20%), 347 (10%), 304 (9%), 281 (8%), 244 (32%), 219 (8%), 199 (9%), 158 (9%), 131 (23%), 130 (100%), 109 (57%), 105 (27%), 97 (16%); Analysis calculated for C₂₈ H₂₈ N₃ O₃ F: C, 71.02; H, 5.96; N, 8.87%. Found: C, 71.16; H, 6.01; N, 8.87%.

EXAMPLE 48 3-Furanylmethyl[R-(R*,S*)-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR95## Step 1

See Method for Example 42. Product chromatographed using 14% EtOAc/Hexane then crystallized from EtOAc to give pure product (1.87 mg, 71%); mp 56.5-57.5° C.;

IR (film): 1766 (CO, carbonate), 1617, 1594, 1525, 1348 (NO₂), 1214, 1161, 863 cm⁻¹ ; NMR (CDCl₃): δ 5.18 (2H, s, PhCH₂); 6.51 (1H, d, J=1.1 Hz, furan C₄ -H); 7.37 (2H, d, J=9.2 Hz, CH meta to NO₂); 7.45 (1H, s, furan C₂ or C₅ -H); 7.57 (1H, s, furan C₂ or C₅ -H); 8.27 (2H, d, J=9.2 Hz, CH ortho to NO₂); Analysis calculated for C₁₂ H₉ NO₆ : C, 54.76; H, 3.45; N, 5.32%. Found: C, 54.68; H, 3.45; N, 5.32%.

Step 2

See Method for Example 42 except used 158 mg (0.6 mmol) of carbonate. Crude product chromatographed using normal phase silica with 1% MeOH n-dichloromethane as eluent then crystallized from ether to give product (164 mg, 74%); mp 126-128° C.;

[α]_(D) ²¹ =+4.9° (c=1, MeOH); IR (film): 3332 (br, NH), 1709 (CO, urethane), 1652 (CO, amide), 1495, 1456, 1247, 1066, 1020, 874, 742 cm⁻¹ ; NMR (CDCl₃): δ 1.32 (3H, d, J=6.9 Hz, CHCH₃); 1.61 (3H, s, CCH₃); 3.25 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.45 (1H, d, J=14.8 Hz, one of CH₂ indole); 4.93 (2H, s, CH₂ O); 5.02 (1H, p, J=7.2 Hz, NHCHCH₃); 5.32 (1H, s, OCONH); 6.30-6.40 (1H, m, CHNH); 637 (1H, s, furan C₄ -H); 6.81 (1H, d, J=2.2 Hz, indole C₂ H); 7.05-7.35 (9H, m, aromatics); 7.43 (1H, s, furan CH); 7.58 (1H, d, J=7.8 Hz, indole C₄ -H); 8.02 (1H, s, indole NH); MS m/e (CI⁺): 446 (M⁺ +l, 7%), 445 (2%), 402 (12%), 316 (11%), 304 (26%), 253 (12%), 244 (6%), 199 (8%), 191 (10%), 131 (23%), 130 (100%), 105 (51%), 81 (34%); Analysis calculated for C₂₆ H₂₇ N₃ O₄ : C, 70.10; H, 6.11; N, 9.43%. Found: C, 70.13; H, 6.13; N, 9.46%.

EXAMPLE 49 2-Furanylmethyl [R,(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR96## Step 1

See Method for Example 42, however, product was unstable and no pure sample was obtained. Used in the next step after chromatography on normal phase silica using 12.5% EtOAc/Hexane estimated purity >90%; NMR (CDCl₃): δ 5.26 (2H, s, CH₂ O); 6.37-6.45 (1H, m, H₄ on ring); 6.54 (1H, d, J=3.2 Hz, H₃ on ring); 7.38 (2H, d, J=9.2 Hz, H meta to NO₂ Group); 7.43-7.50 (1H, m, H₅ on ring); 8.27 (2H, d, J=9.1 Hz, H ortho to NO₂ group);

Step 2

See Method for Example 42 except used 158 mg (0.6 mmol) of carbonate. Crude product chromatographed on normal phase silica using 1% MeOH/CH₂ Cl₂ then crystallized from ether to give product (95 mg, 43%);

mp 133-140.5° C.; [α]_(D) ²¹ =+9.0° (c=0.5, MeOH); IR (film): 3331 (br, NH), 1713 (CO, urethane), 1652 (CO, amide), 1495, 1248, 1068, 742 cm⁻¹ ; NMR (CDCl₃): δ 1.33 (3H, d, J=6.9 Hz, CHCH₃); 1.61 (3H, s, CCH₃); 3.24 (1H, d, J=14.7 Hz, one the CH₂ indole); 3.46 (1H, d, J=14.8 Hz, one of CH₂ indole); 4.95-5.10 (3H, m, CH₂ O and CONHCH); 5.31 (1H, s, OCONH); 6.30-6.40 (3H, m, CONHCH, furan C₃ and C₄ -H); 6.80 (1H, d, J=7.2 Hz, indole C₂ H); 7.05-7.35 (8H, m, aromatics); 7.38 (1H, s, furan C₅ -H); 7.57 (1H, d, J=8.1 Hz, indole C₄ -H); 7.99 (1H, s, indole NH); MS m/e (CI⁺ : 446 (M⁺ +1, 23%), 445 (M⁺, 11%), 402 (66%), 348 (16%), 316 (16%), 304 (82%), 253 (22%), 244 (24%), 191 (36%), 130 (100%), 105 (88%), 81 (49%); Analysis calculated for C₂₆ H₂₇ N₃ O₄ : C, 70.10; H, 6.11; N, 9.43%. Found: C, 70.09; H, 6.16; N, 9.37%.

EXAMPLE 50 (3-Fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR97##

To a stirred solution of 3-fluorobenzyl alcohol (189 mg, 1.5 mmol) and triphosgene (178 mg, 0.6 mmol) under an atmosphere of N₂ at 0° C. (ice bath) in CH₂ Cl₂ (10 mL, anhydrous) was added a solution of pyridine (119 mg, 1.5 mmol) in CH₂ Cl₂ (2 mL, anhydrous). IR recorded after 5 and 30 minutes indicated no change with chloroformate at 1776 cm⁻¹. Solvent removed under vacuum at 30° C. using a 20% NaOH trap for excess phosgene, added EtOAc (20 mL), and filtered of pyridine hydrochloride. Removed solvent under reduced pressure and added about half of chloroformate to a stirred solution of α-metryptophanyl-1-phenethyl amide (160 mg, 0.5 mmol) and pyridine (40 mg, 0.5 mmol) in THF (20 mL, anhydrous). Precipitate formed immediately and after 5 minutes H₂ indicated no starting amine remaining. Removed solvent under reduced pressure and added 50 mL of EtOAc. Organic phase washed successively with 10% citric acid solution (2×30 mL), H₂ O (30 mL), saturated NaHCO₃ (2×30 mL), H₂ O (2×30 mL), brine (30 mL), then dried over MgSO₄. Product recrystallized from ether to give pure product (0.2 g, 84%); mp 109-112.5° C.;

[α]_(D) ²¹° C. =+8.5° (c=1, MeOH); IR (film): 3334 (br, NH str), 1717 (CO, urethane), 1653 (CO, amide); 1592, 1491, 1456, 1256, 1070, 744 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CH₃ CH); 1.63 (3H, s, CH₃ C); 3.27 (1H, d, J=14.8 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.6 Hz, one of CH₂ indole); 4.95-5.05 (1H, m, NHCHCH₃); 5.05 (2H, s, CH₂ O); 5.46 (1H, s, OCONH); 6.29 (1H, d, J=7.3 Hz, CONHCH); 6.81 (1H, s, indole C₂ -H); 6.95-7.30 (11H, m, aromatics); 7.34 (1H, d, J=8.0 Hz, indole C₇ -H); 7.58 (1H, d, J=7.9 Hz, indole C₄ -H); 8.01 (1H, s, indole NH); Ms m/e (CI⁺): 475 (M⁺, 2.27%), 474 (M⁺ +H, 85%); 473 (M⁺, 13%); 353 (12%); 348 (14%); 348 (14%); 344 (28%); 305 (16%); 304 (67%); 281 (29%); 244 (23%); 199 (14%); 131 (44%); 130 (100%); Analysis calculated for C₂₈ H₂₈ N₃ O₃ F: C, 71.02; H, 5.96; N, 8.87%. Found: C, 71.01; H, 6.00; N, 8.87%.

EXAMPLE 51 (4-Fluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR98##

See Method for Example 50. Crystallization from ether gave pure product (191 mg, 81%); mp 101-111° C.;

[α]_(D) ²¹ =+7.9 (c=0.5, MeOH); IR (film): 3327 (br, NH str), 1716 (CO, urethane), 1653 (CO, amide), 1511, 1457, 1225, 1071, 825, 743 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CH₃ CH); 1.62 (3H, s, CH₃ C); 3.26 (1H, d, J=14.8 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.8 Hz, one of CH₂ indole); 4.95-5.05 (1H, m, CONCHCH₃); 5.02 (2H, s, CH₂ O); 5.39 (1H, s, OCONH); 6.25-6.35 (1H, br.d, CONHCH); 6.80 (1H, s, indole C₂ -H); 6.95-7.30 (11H, m, aromatics); 7.34 (1H, d, J=7.8 Hz, indole C₇ -H); 7.58 (1H, d, J=7.9 Hz, indole C₄ -H); 7.99 (1H, s, indole NH); MS m/e (CI⁺): 475 (M⁺ +2, 22%), 474 (M⁺ +H, 68%), 473 (M⁺, 10%), 430 (35%), 348 (29%), 344 (31%), 305 (22%), 304 (83%), 281 (23%), 244 (36%), 131 (60%), 130 (100%); Analysis calculated for C₂₈ H₂₈ N₃ O₃ F: C, 71.02; H, 5.96; N, 8.87%. Found: C, 70.80; H, 5.93; N, 8.69%.

EXAMPLE 52 (2,3-Difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-methyl)-1-methyl-2-oxo-[(1-phenylethyl)amino]ethyl]-carbamate ##STR99##

See method for Example 50. Crude product chromatographed using 2% MeOH/CH₂ Cl₂ the crystallized from ether to give pure product (232 mg, 94%);

mp 96-102° C.; [α]_(D) ²¹ =+6.7° (c=0.5, MeOH); IR (film): 3336 (br, NH str), 1716 (CO, urethane), 1652 (CO, amide), 1492, 1457, 1288, 1250, 1069, 741 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CH₃ CH); 1.60 (3H, s, CCH₃); 3.27 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.6 Hz, one of CH₂ indole); 4.95-5.05 (1H, m, NHCHCH₃); 5.13 (1H, d, J=13.0 Hz, one of CH₂ O); 5.18 (1H, d, J=13.4 Hz, one of CH₂ O); 5.49 (1H, s, OCONH); 6.29 (1H, d, J=7.2 Hz, NHCH); 6.84 (1H, s, indole C₂ H); 6.95-7.35 (11H, m, aromatics); 7.58 (1H, d, J=7.7 Hz, indole C₄ -H); 8.10 (1H, s, indole NH); MS m/e (CI⁺): 493 (M⁺ +2, 10%), 492 (M⁺ +1, 4%), 491 (M⁺, 5%), 371 (11%), 348 (19%), 305 (17%), 304 (54%), 299 (18%), 244 (22%), 199 (12%), 144 (40%), 1310 (98%), 127 (100%), 105 (78%); Analysis calculated for C₂₈ H₂₇ N₃ O₃ F₂ : C, 68.42; H, 5.54; N, 8.55%. Found: C, 68,43; H, 5.64; N, 8.51%.

EXAMPLE 53 (2,4-Difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]-ethyl]carbamate ##STR100##

See Method for Example 50. Crude product chromatographed using 2% MeOH/CH₂ Cl₂ then crystallized from ether to give pure product (240 mg, 98%);

mp 77-87° C.; [α]_(D) ²¹ =+5.6 (c=1, MeOH); IR (film): 3332 (br, NH str), 1713 (CO, urethane), 1651 (CO, amide), 1507, 1250, 1140, 1101, 1071, 742 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CH₃ CH); 1.03 (3H, s, CCH₃); 3.27 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.46 (1H, d, J=14.9 Hz, one of CH₂ indole); 4.95-5.05 (1H, m, CHCH₃); 5.09 (2H, s, CH₂ O); 5.43 (1H, s, OCONH); 6.23-6.33 (1H, br.d, CONHCH); 6.75-6.90 (3H, m, aromatics); 7.05-7.35 (9H, m, aromatics); 7.58 (1H, d, J=7.8 Hz, indole C₄ -H); 8.01 (1H, s, indole NH); MS m/e (CI⁺): 493 (M⁺ +2, 11%), 492 (M⁺ +1, 40%), 491 (M⁺, 7%), 448 (12%), 361 (26%), 348 (15%), 304 (56%), 299 (15%), 244 (33%), 199 (14%), 144 (36%), 131 (45%), 130 (100%), 127 (93%), 105 (70%);

Analysis calculated for C₂₈ H₂₇ N₃ O₃ F₂ : C, 68.42; H, 5.54; N, 8.55%. Found: C, 68.66; H, 5.63; N, 8.45%.

EXAMPLE 54 (2,5-Difluorophenyl)methyl[R-(R*,S*)]-[1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]-ethyl]carbamate ##STR101##

See Method for Example 50. Crystallization from ether gave pure product (229 mg, 95%); mp 121-122° C.;

[α]_(D) ²¹ =+6.0 (c=0.5, MeOH); IR (film): 3336 (br, NH str), 1721 (CO, urethane), 1656 (CO, amide), 1496, 1457, 1246, 1191, 1144, 1072, 909, 741 cm⁻¹ ; NMR (CDCl₃): δ 1.29 (3H, d, J=6.9 Hz, CH₃ CH); 1.64 (3H, s, CCH₃); 3.28 (1H, d, J=14.7 Hz, one of CH₂ indole); 3.47 (1H, d, J=14.0 Hz, one of CH₂ indole); 4.95-5.05 (1H, m, NHCHCH₃); 5.08 and 5.14 (each 1H, each d, each one of CH₂ O, J=13.4 Hz); 5.51 (1H, s, OCONH); 6.28 (1H, d, J=7.6 Hz, CONHCH); 6.85 (1H, d, J=2.1 Hz, indole C₂ H); 6.90-7.33 (10H, m, aromatics); 7.34 (1H, d, J=8.0 Hz, indole C₇ -H); 7.58 (1H, d, J=7.8 Hz, indole C₄ -H); 8.05 (1H, s, indole NH); MS m/e (CI⁺): 493 (M⁺ +2, 14%), 492 (M⁺ +1, 55%), 491 (M⁺, 6%), 362 (12%), 348 (31%), 347 (17%), 304 (39%), 244 (40%), 131 (50%), 130 (100%), 127 (65%), 105 (66%); Analysis calculated for C₂₈ H₂₇ N₃ O₃ F₂ : C, 68.42; H, 5.54; N, 8.55%. Found: C, 68.17; H, 5.46; N, 8.35%.

EXAMPLE 55 Phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-(1H-indazol-3-ylmethyl-)-2-oxo-2-[(1-phenylethyl)-amino]ethyl]carbamate ##STR102## Step 1: N-Benzyloxycarbonyltryptazan

A mixture of tryptazan (PD 018111) (0.09 g, 0.44 mmol), sodium hydrogen carbonate (0.13 g, 1.55 mmol), dibenzyldicarbonate (0.18 g, 0.63 mmol), water (5 mL), and dioxan (5 mL) was stirred at room temperature overnight. The mixture was diluted with water, washed twice with ether, acidified with 1N hydrochloric acid, and extracted with ethyl acetate. The combined extracts were washed with water, dried over MgSO₄, filtered, and evaporated to dryness. Recrystallization from ethyl acetate/hexane gave colorless crystals (0.12 g).

Step 2: Phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-(1H-indazol-3-ylmethyl-)-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate

To a solution of N-benzyloxycarbonyl tryptazan (0.12 g, 0.35 mmol) in ethyl acetate (20 mL) was added hydroxybenzotriazole hydrate (0.058 g, 0.38 mmol) followed by dicyclohexylcarbodiimide (0.075 g, 0.36 mmol). After stirring at room temperature for 3 hours, the mixture was filtered and (S)-α-methylbenzylamine (0.055 g, 0.45 mmol) in ethyl acetate (5 mL) was added to the filtrate. After stirring at room temperature overnight, the reaction mixture was washed with saturated sodium bicarbonate solution, 1N hydrochloric acid, and water. The solution was then dried over magnesium sulphate, filtered, and evaporated to dryness. The residue was purified by reverse phase chromatography eluting with methanol/water mixtures to give the title compound (0.070 g, 45%); mp 116-120° C.;

NMR (300 MHz, CDCl₃): δ 1.23 (3H, d, J=6.9 Hz); 3.32 (1H, dd, J=15.0, 7.3 Hz); 3.59 (1H, ddd, J=15.0, 9.7, and 4.8 Hz); 4.70-4.80 (1H, m); 4.85-4.95 (1H, m); 5.11 (2H, s); 6.14 (0.5H d, J=7.4 Hz); 6.20 (0.5H, d, J=7.1 Hz); 6.60-6.85 (1H, m); 6.90-7.40 (14H, m); 7.70-7.80 (1H, m); Analysis calculated for C₂₆ H₂₆ N₄ O₃ : C, 70.57; H, 5.92; N, 12.66%. Found: C, 70.41; H, 5.97; N, 12.60%.

EXAMPLE 56 Phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-[(5-fluoro-1H-indol-3-yl)methyl]-2-oxo-2-[(1-phenylethyl)amino]-ethyl]carbamate ##STR103## Step 1: N-Benzyloxycarbonyl-5-fluoro-RS-tryptophan

Dibenzyldicarbonate (0.39 g, 3.1 mmol) was dissolved in dioxan (15 mL) and added to a stirred suspension of 5-fluoro tryptophan (0.58 g, 2.6 mmol) and sodium bicarbonate (0.67 g, 8.0 mmol) in water (15 mL). After stirring at room temperature overnight, the reaction mixture was diluted with water and washed with ether twice, acidified with 1N hydrochloric acid, and extracted three times with ethyl acetate. The combined extracts were washed with water, dried MgSO₄, sulphate, filtered, and evaporated. Recrystallization from ethyl acetate and hexane gave colorless crystals (0.75 g, 81%); mp 126-128° C.;

NMR (300 MHz, DMSO-d₆): δ 2.96 (1H, dd, J=14.4 and 9.6 Hz); 3.14 (1H, dd, J=14.5 and 4.4 Hz); 4.15-4.25 (1H, m); 4.97 (2H, s); 6.90 (1H, dt, J=9.2 and 2.5 Hz); 7.10-7.35 (8H, m); 7.55 (1H, d, J=8.1 Hz); 10.94 (1H, s); 12.6 (1H, bs); Analysis calculated for C₁₉ H₁₇ FN₂ O₄ : C, 64.04; H, 4.81; N, 7.86. Found: C, 64.02; H, 4.80; N, 7.84.

Step 2: Phenylmethyl[R-(R*,S*)] and [S-(R*,R*)]-[1-[(5-fluoro-1H-indol-3-yl)methyl]-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate

To a solution of N-benzyloxycarbonyl-5-fluoro-tryptophan (0.15 g, 0.42 mmol) in ethyl acetate (25 mL) was added 1-hydroxybenzotriazole hydrate (0.06.6 g, 0.43 mmol) followed by dicyclohexylcarbodiimide (0.089 g, 0.43 mmol). After stirring at room temperature for 2 hours, the mixture was filtered and to the filtrate was added a solution of (S)-α-methylbenzylamine (0.065 g, 0.54 mmol) in ethyl acetate (5 mL). After stirring at room temperature for 48 hours, the solution was washed with saturated sodium bicarbonate solution, 1N hydrochloric acid solution, and water. After drying over magnesium sulphate, the solution was filtered, dried, and evaporated. The residue was purified by reverse phase chromatography to give the title compound (0.15 g, 78%); mp 152-155° C.;

NMR (300 MHz, CDCl₃): δ 1.18 (1.5H, d, J=6.9 Hz); 1.32 (1.5H, d, J=6.9 Hz); 3.00-3.15 (1H, m); 3.20-3.35 (1H, m); 4.35-4.50 (1H, m); 4.90-5.05 (1H, m); 5.10 (2H, s); 5.35-5.50 (1H, m); 5.70-5.80 (1H, m); 6.78 (0.5H, d); 6.90-7.05 (3.5H, m); 7.20-7.35 (10H, m); 7.80 (0.5H, S); 8.02 (0.5H, s); Analysis calculated for C₂₇ H₂₆ FN₃ O₃ : C, 70.57; H, 5.70; N, 9.14%. Found: C, 70.67; H, 5.67; N, 9.09%.

EXAMPLE 57 Phenylmethyl[1-(1-methyl-1H-indol-3-ylmethyl]-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR104## Step 1: CBZ-1-methyl-DL-tryptophan

1-Methyl-DL-tryptophan was suspended in H₂ O/dioxan (20 mL) and NaHCO₃ (0.072 g, 8 mmol) added. A solution of dibenzyldicarbonate (1.37 g, 4.8 mmol) was added and the reaction was stirred at room temperature overnight. The solution was diluted with water then washed with ether. The aqueous was then acidified to pH 1 with concentrated HCl and extracted with ethylacetate. The combined organic extracts were washed with water, dried over MgSO₄, and the solvent removed in vacuo. The brown oil obtained was purified by reverse phase chromatography (0.800 g, 65%); mp 58-60° C.;

[α]_(D) ²⁰ =0 (c=0.25, MeOH); IR (film): 1716 (urethane CO), 1507 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.99 (1H, d×d, J=14.7, 9.5 Hz, one of βCH₂); 3.16 (1H, d×d, J=14.7 and 4.5 Hz, one of βCH₂); 3.71 (3H, s, NCH₃); 4.32 (1H, m, αCH); 4.97 (2H, s, CH₂ Ph); 7.01-7.65 (11H, m, aromatic protons, urethane NH); 12.65 (1H, s, br, CO₂ H); MS m/e (CI): 353 MH⁺ ; Analysis calculated for C₂₀ H₂₀ N₂ O₄ : C, 68.17; H, 5.72; N, 7.95%. Found: C, 67.80; H, 5.86; N, 8.19%.

Step 2: CBZ-1-Methyl-DL-tryptophan-(+)-α-methylbenzylamine

CBZ-1-methyl-DL-tryptophan (0.39 g, 1.2 mmol), HBTU (0.91 g, 1.2 mmol), and diisopropylethylamine (0.42 mL, 2.4 mmol) were dissolved in DCM (3 mL) and the solution stirred for 10 minutes at room temperature. The (±)-α-methylbenzylamine (0.15 mL, 1.2 mmol) was added and the reaction was stirred for a further 4 hours. The solvent was removed in vacuo and the resulting residue redissolved in ethylacetate. The organic was washed with 5% HCl, 5% NaHCO₃, water, and brine. The organic layer was then dried over MgSO₄ and the solvent removed in vacuo. The crude material was purified by medium pressure chromatography, ethylacetate/hexane (0.076 g, 14%); mp 69.5-71.8° C.;

[α]_(D) ²⁰ =0 (c=0.5, MeOH); IR (film): 1712 (urethane CO), 1687 (urethane CO), 1652 (amide I), 1548 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.23, 1.34 (3H, 2×d, J=6.9 and 7.5 Hz, CH₃); 2.84-3.19 (2H, m, βCH₂); 3.66; 3.71 (3H, 2×s, N--CH₃); 4.32-4.37 (1H, m, CH); 4.86-4.97 (3H, m, PhCH₂, CH); 6.87-7.66 (16H, m, Ph×2, indole aromatics, urethane NH); 8.32-8.41 (1H, 2×d, J=7.7 and 7.9 Hz, amide NH); MS m/e (CI): 456.3 MH⁺ ; Analysis calculated for C₂₈ H₂₉ N₃ O₃ : C, 73.82; H, 6.42; N, 9.22%. Found: C, 73.89; H, 6.57; N, 8.95%.

EXAMPLE 58 Phenylmethyl[R-(R*,S*)]-[1-(2-naphthalenylmethyl-2-oxo-2-[(1-phenylmethyl)amino]ethyl]carbamate ##STR105## Step 1: CBZ-D-3-(1-naphthyl)alanine

See Method for CBZ-1-methyl-DL-tryptophan in Example 57 (0.17 g, 22%);

IR (film): 1709 (urethane CO), 1532 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 2.97-3.23 (2H, m, βCH₂); 4.32 (1H, m, αCH); 4.94 (2H, s, PhCH₂); 7.21-7.89 (13H, m, aromatics, urethane NH).

Step 2: CBZ-D-3-(2-naphthyl)alanine-3-(-)-α-methyl-benzylamine

See Method as for the 1-methyl-DL-tryptophan derivative (0.081 g, 14%); mp 100.2-102.7° C.;

[α]_(D) ²⁰ =-26° (c=0.25, MeOH); IR (film): 1709 (urethane CO), 1656 (amide I), 1537 cm⁻¹ (amide II); NMR (DMSO-d₆): δ 1.24 (3H, d, J=7.0 Hz, CH₃); 2.97 (1H, d×d, J=13.4 and 9.9 Hz, one of βCH₂); 3.13 (1H, d×d, J=13.4 and 5.0 Hz, one of βCH₂); 4.42 (1H, m, αH, methylbenzylamine); 4.89 (3H, m, PhCH₂, αCH); 7.23-7.48 (14H, m, naphthyl H₃,6,7, Ph×2, urethane NH); 7.84 (4H, m, naphthyl H₁,4,5,8); 8.38 (1H, d, J=8.0 Hz, amide NH); MS m/e (CI): 453 MH⁺ ; Analysis calculated for C₂₉ H₂₈ N₂ O₃ : C, 76.34; H, 6.41; N, 6.36%. Found: C, 76.74; H, 6.22; N, 6.06%.

EXAMPLE 59 1-Phenylethyl N-[(phenylmethoxy)carbonyl]-DL-tryptophan ##STR106##

To a solution of N-benzyloxycarbonyl-RS-tryptophan (1.07 g, 3.16 mmol), (S)-sec-phenethyl alcohol (0.39 g, 3.19 mmol) and dimethylaminopyridine (0.04 g, 0.33 mmol) in ethyl acetate (60 mL) was added dicyclohexylcarbodiimide (0.65 g, 3.16 mmol). After stirring at room temperature overnight, the mixture was filtered and evaporated to dryness. Purification by column chromatography eluting with 2% ethyl acetate in dichloromethane gave a colorless gum (1.1 g, 79%);

NMR (300 MHz, CDCl₃): δ 1.41 and 1.49 (3H, two d, J=6.5 Hz); 3.10-3.30 (2H, m); 4.70-4.80 (1H, m); 5.00-5.15 (2H, m); 5.20-5.35 (1H, m); 5.80-5.95 (1H, two m); 6.49 and 6.89 (1H, two s); 7.00-7.35 (13H, m); 7.42 (0.5H, d, J=8.0 Hz); 7.55-7.60 (0.5H, m); 7.81-7.94 (1H, two s); Analysis calculated for C₂₇ H₂₆ N₂ O₄ : C, 73.29; H, 5.92; N, 6.33%. Found: C, 73.03; H, 6.01; N, 6.21%.

EXAMPLE 60 Phenylmethyl[1-(benzo[b]thien-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]carbamate ##STR107## Step 1: Methyl N-CBZ-α-methyl-3-benzothiophenylalanine

A solution of methyl α-methyl-3-benzothiophenylalanine (Horwell, et al., WO9204025 A1. Mar. 19, 1992) (0.5 g, 2.0 mmol), sodium hydrogen carbonate 1:0.50 g, 6.00 mmol), dibenzyldicarbonate (0.7 g, 2.4 mmol), water (10 mL), and dioxan (10 mL) was stirred at room temperature overnight. The reaction mixture was diluted with water and ether. The organic phase was separated, washed with water, dried over MgSO₄, filtered, and evaporated to dryness. Purification by column chromatography eluting with 2% ethyl acetate in dichloromethane gave an oil (0.6 g, 78%);

NMR (300 MHz, CDCl₃): δ 1.68 (3H, s); 3.48 (1H, d, J=14.5 Hz); 3.60-3.75 (4H, m); 5.05-5.20 (2H, m); 5.53 (1H, bs); 6.94 (1H, s); 7.20-7.40 (7H, m); 7.65-7.75 (1H, m); 7.80-7.85 (1H, m); Analysis calculated for C₂₁ H₂₁ NO₄ S: C, 65.78; H, 5.52; N, 3.65%. Found: C, 65.85; H, 5.50; N, 3.49%.

Step 2: N-CBZ-α-methyl-3-benzothiophenylalanine

A solution of methyl N-CBZ-α-methyl-3-benzothiophenylalanine (0.6 g, 1.57 mmol), lithium hydroxide hydrate (0.14 g, 3.33 mmol) in water (20 mL), and dioxan (20 mL) was stirred at room temperature overnight. The reaction mixture was diluted with water, washed with ether, acidified with 1N hydrochloric acid, and extracted with ethyl acetate three times. The combined extracts were washed with water, dried over magnesium sulphate, filtered, and evaporated to dryness. Crystallization from ether/hexane gave colorless crystals 0.48 g (83%);

mp 133-135° C.; NMR (300 MHz, CDCl₃): δ 1.28 (3H, s); 3.27 (1H, d, J=14.4 Hz); 3.59 (1H, d, J=14.4 Hz); 5.02 (1H, d, J=12.6 Hz); 5.08 (1H, d, J=12.3 Hz); 7.25-7.40 (8H, m); 7.75 (1H, d, J=7.9 Hz); 7.90-8.00 (1H, m); 12.6 (1H, s); Analysis calculated for C₂₀ H₁₉ NO₄ S: C, 65.02; H, 5.15; N, 3.79%. Found: C, 64.99; H, 5.15; N, 3.80%.

Step 3: Phenylmethyl[1-(benzo[b]thien-3-ylmethyl)-1-methyl-2-oxo-2-(1-phenylethyl)amino]ethyl]-carbamate

To a solution of N-CBZ-α-methyl-3-benzothiophenylalanine (0.12 g, 0.33 mmol) in ethyl acetate (10 mL) was added hydroxybenzotriazole hydrate (0.055 g, 0.36 mmol) and followed by dicyclohexylcarbodiimide (0.072 g, 0.35 mmol). After stirring at room temperature for 15 minutes, the mixture was filtered and (S)-sec-phenylethylamine (0.051 g, 0.42 mmol) in ethyl acetate was added to the filtrate. After stirring at room temperature overnight, the mixture was diluted with ethyl acetate and washed with saturated sodium hydrogen carbonate solution, 1N hydrochloric acid solution and water. The solution was dried over magnesium sulphate, filtered, and evaporated to dryness. Purification by column chromatography eluting with dichloromethane/ethyl acetate 98:2 and crystallization from ether gave colorless crystals (0.09 g, 58%); mp 147-150° C.;

NMR (300 MHz, DMSO-d₆): δ 1.20-1.40 (6H, m); 3.30-3.60 (2H, m); 4.85-4.95 (1H, m); 5.05 (2H, s); 7.00-7.40 (14H, m); 7.75-7.90 (1H, m); 7.90-7.95 (1H, m); 8.0 and 8.1 (1H, two d).

EXAMPLE 61 Phenylmethyl[R-(R*,R*)]-[1-(4,5-dihydro-4-phenyl-2-thiazoly-1)-2-(1H-indol-3-yl)-1-methylethyl]carbamate ##STR108##

A solution of Z-α-Me-R-tryphophanyl-R-phenyl-glycinol (0.14 g, 0.30 mmol) in toluene (20 mL) was treated with Lawesson's reagent (0.2 g, 0.5 mmol) and the mixture heated at reflux for 90 minutes. The crude reaction mixture was loaded onto a silica gel column and eluted with CH₂ Cl₂, then Et₂ O. Further purification was then carried out using reverse phase silica gel and 85% MeOH in H₂ O as eluant to give the product as a white foam (0.08 g, 57%); mp 64-66° C.;

[α]_(D) ²⁰ =-3° (c=0.25, MeOH); IR (film): 3391, 1715, 1617, 1496, 1456 cm⁻¹ ; NMR (DMSO-d₆): δ 1.41 (3H, s); 2.94 (1H, br.t); 3.30 (1H, obscured by H₂ O); 3.54 (1H, d, J=13.9 Hz); 3.71 (1H, br.t); 5.09 (2H, m); 5.46 (1H, m); 6.92 (1H, t, J=7.1 Hz); 7.00-7.39 (13H, m); 7.53 (1H, d, J=7.8 Hz); 7.58 (1H, br.s); 10.92 (1H, br.s); Analysis calculated for C₂₈ H₂₇ N₃ O₂ S.0.25H₂ O: C, 70.93; H, 5.85; N, 8.86%. Found: C, 70.93; H, 5.73; N, 8.84%.

EXAMPLE 62 (See Scheme X) Phenylmethyl[1-(cyanomethyl)-1-(1H-indol-3-ylmethyl)-2-oxo-2-[(1-phenylethyl)amino]-ethyl]carbamate ##STR109## Step 1

RS-Tryptophanmethylester (2.03 g, 9.30 mmol) was stirred and dissolved in formic acid (15 mL) at room temperature. To this was added acetic anhydride (4.4 mL, 46.5 mmol) in one portion and the mixture stirred for 2.5 hours. The solution was poured into water (100 mL) and the mixture neutralized by the addition of Na₂ CO₃. The product was extracted into EtOAc (2×100 mL) and the combined extracts washed with saturated NaHCO₃ solution (50 mL) and once with brine (50 mL). The EtOAc solution was dried over MgSO₄, filtered, and the solvent removed in vacuo to give the product as a syrup. This was crystallized from 50% EtOAc/50% n-hexane as a white solid 11.55 g, 68%); mp 113-119° C.;

IR (film): 3370, 2920, 1740, 1672, and 1212 cm⁻¹ ; NMR (CDCl₃): δ 3.29-3.41 (2H, m, CH₂ indole); 3.71 (3H, s, CO₂ CH₃); 5.00-5.05 (1H, m, CH₂ CH); 6.13 (1H, b, NHCHO); 6.98 (1H, s, indole-H₂); 7.09-7.21 (2H, m, indole-H₅ H₆); 7.35 (1H, d, J=8.0 Hz indole-H₇); 7.53 (1H, d, J=7.8 Hz, indole-H₄); 8.14 (1H, s, NHCHO); 8.20 (1H, b, indole-NH).

Step 2

N-Formyl-RS-tryptophanmethylester (1.50 g, 6.09 mmol) was stirred and dissolved in anhydrous DMF (20 mL) and cooled in an ice bath. 4-Dimethylaminopyridine (0.075 g, 0.61 mmol) was added followed by dropwise addition of ditertbutyldicarbonate (1.33 g, 6.09 mmol) in anhydrous DMF (20 mL) added over 1 hour. The cold solution was stirred for 18 hours with slow rewarming to room temperature. The mixture was poured into water (300 mL) and extracted with Et₂ O (3×100 mL). The combined Et₂ O extracts were washed with water (3×100 mL), dried over MgSO₄, filtered and the solvent removed in vacuo. The residue was purified by chromatography on silica using 50% n-hexane/50% EtOAc as eluant giving the product as a white solid (1.71 g, 81%); mp 61-62° C.;

IR (film): 3306, 2979, 1733, 1688, 1454, 1371, and 1158 cm⁻¹ ; NMR (CDCl₃): δ 1.66 (9H, s, ##STR110## ; 3.20-3.34 (2H, m, CH₂ indole); 3.71 (3H, s, CO₂ CH₃); 4.98-5.04 (1H, m, CH₂ CHCO₂ CH₃); 6.32 (1H, d, J=7.4 Hz, NHCHO); 7.20-7.33 (2H, m, indole-H₅ H₆); 7.39 (1H, s, indole-H₂); 7.48 (1H, d, J=7.9 Hz, indole-H₄); 8.09 (1H, d, J=8.1 Hz, indole-H₇); 8.18 (1H, s, NHCHO).

Step 3

BOC-N-formyl-RS-tryptophanmethylester (3.25 g, 9.38 mmol) was stirred and dissolved in CH₂ Cl₂ (75 mL) and cooled in an ice bath. Et₃ N (7.84 mL, 56.28 mmol) was added followed by a solution of triphosgene (1.02 g, 3.44 mmol) in CH₂ Cl₂ (25 mL) added dropwise over 45 minutes. The cold solution was stirred for 3 hours with slow rewarming to room temperature. The CH₂ Cl₂ solution was then washed with 5% citric acid solution (3×25 mL), saturated NaHCO₃ solution (25 mL) and brine (25 mL), dried over MgSO₄, filtered, and the solvent removed in vacuo. The residue was purified by chromatography on silica using 67% n-hexane/33% EtOAc as eluant giving the product as an off-white solid (2.26 g, 73%); mp 90-91° C.;

IR (film): 2980, 2149, 1760, 1733, 1454, 1372, 1157, and 1088 cm⁻¹ ; NMR (CDCl₃): δ 1.67 (9H, s, ##STR111## ; 3.28 (1H, dd, J=14.7 and 8.0 Hz, CHH indole); 3.41 (1H, dd, J=14.7 and 4.9 Hz, CHH indole); 3.79 (3H, s, CO₂ CH₃); 4.54-4.58 (1H, m, CH₂ CHCO₂ CH₃); 7.23-7.36 (2H, m, indole-H₅ H₆); 7.50 (1H, d, J=7.8 Hz, indole-H₄); 7.59 (1H, s, indole-H₂); 8.16 (1H, d, J=8.2 Hz, indole-H₇).

Step 4

1,3-Dimethyl-3,4,5-tetrahydro-2(1H)-pyrinidinone (DMPU) (0.121 mL, 1.0 mmol) was added to a stirred solution of the isonitrile (0.328 g, 1.0 mmol) in anhydrous THF (10 mL) at -78° C. To this was added lithiumhexamethyldisilazide (1.1 mL, 1.0 mmol, 1.1 mmol) and the mixture stirred for 30 minutes. Bromoacetonitrile (0.077 mL, 1.1 mmol) was added and the mixture stirred for 1 hour at -78° C. and then at room temperature for 1.5 hours. The mixture was poured into water (25 mL) and extracted with Et₂ O (2×25 mL), the combined extracts washed once with brine (25 mL), the Et₂ O dried over MgSO₄, filtered, and the solvent removed in vacuo. The residue was purified by chromatography on silica using 75% n-hexane/25% EtOAc as eluant giving the product as a white solid (0.315 g, 86%); mp 92-93° C.;

IR (film): 2981, 1737, 1454, 1371, 1259, and 1156 cm⁻¹ ; NMR (CDCl₃): δ 1.68 (9H, s, CO₂ C(CH₃)₃); 2.9 (1H, d, J=16.7 Hz, indole CHH); 3.09 (1H, d, J=16.8 Hz indole CHH); 3.47 (2H, d, J=3.7 Hz, CH₂ CN); 3.76 (3H, s, CO₂ CH₃); 7.24-7.37 (2H, m, indole-H₅ H₆); 7.51 (1H, d, J=7.6 Hz, indole-H₄); 7.62 (1H, s, indoles-H₂); 8.15 (1H, d, J=8.1 Hz, indole-H₇); Analysis calculated for C₂₀ H₂₁ N₃ O₄ : C, 65.38; H, 5.76; N, 11.44%. Found: C, 65.23; H, 5.90; N, 11.36%.

Step 5

4.7 M HCl in 1,4-dioxan (1.0 mL, 4.7 mmol) was added to a stirred solution of the isonitrile (0.413 g, 1.12 mmol) in EtOAc (10 mL) cooled to 5° C. To this mixture was added water (1.0 mL) and the solution stirred at room temperature for 1 hour. The solvents were removed in vacuo and the residual solid partitioned between saturated NaHCO₃ solution (10 mL) and EtOAc (2×25 mL). The combined EtOAc extracts were washed once with brine (25 mL), dried over MgSO₄, filtered, and the solvent removed in vacuo. The residue was purified by chromatography on silica using 50% n-hexane/50% EtOAc as eluant giving the product as a syrup (0.301 g, 75%).

IR (film): 3380, 2979, 2256, 1734, 1454, 1370, 1258, 1157 cm⁻¹ ; NMR (CDCl₃): δ 1.67 (9H, s, ##STR112## 1.88 (2H, bs, NH₂); 2.74 (1H, d, J=16.5 Hz, CHHCN); 2.89 (1H, d, J=16.4 Hz, CHHCN); 3.12 (1H, d, J=14.3 Hz, indole CHH); 3.25 (1H, d, J=14.2 Hz, indole CHH); 3.69 (3H, s, CO₂ CH₃); 7.22-7.35 (2H, m, indole-H₅ H₆); 7.46 (1H, s, indole-H₂); 7.52 (1H, d, J=7.6 Hz, indole-H₄); 8.13 (1H, d, J 8.1 Hz, indole-H₇); Analysis calculated for C₁₉ H₂₃ N₃ O₄ O.3H₂ O: C, 63.85; H, 6.49; N, 11.76%. Found: C, 63.82; H, 6.64; N, 11.49%.

Step 6

The amine (0.561 g, 1.57 mmol) was stirred and dissolved in 1,4-dioxan (10 mL) and water (0.5 mL) added. Na₂ CO₃ (0.832 g, 7.85 mmol) was added followed by benzylchloroformate (0.448 mL, 3.14 mmol) and the reaction stirred at room temperature for 1 hour. The 1,4-dioxan was removed in vacuo and the residue partitioned between EtOAc (50 mL) and brine (2×25 mL). The EtOAc solution was dried over MgSO₄, filtered, and the solvent removed in vacuo. The residue was purified by chromatography on silica using 67% n-hexane/33% EtOAc as eluant to give the product as a syrup (0.662 g, 86%);

IR (film): 3342, 2929, 2253, 1732, 1454, 1372, 1156, 1089 cm⁻¹ ; NMR (CDCl₃): δ 1.66 (9H, s, ##STR113## 3.24-3.34 (2H, m, CH₂ CN); 3.47-3.62 (2H, m, CH₂ indole); 3.67 (3H, s, CO₂ CH₃); 5.14 (2H, s, PHCH₂ OCO); 5.78 (1H, s, NHCOO); 7.15-7.20 (1H, m, indole); 7.28-7.43 (12H, m, Ar); 8.10 (1H, d, J=8.4 Hz, indole-H₇); Analysis calculated for C₂₇ H₂₉ N₃ O₆ : C, 65.97; H, 5.95; N, 8.55%. Found: C, 65.72; H, 6.01; N, 8.29%

Step 7

The BOC protected ester (0.119 g, 0.24 mmol) was stirred and dissolved in CH₂ Cl₂ (2 mL) at room temperature. Trifluoroacetic acid (1.0 mL) was added and the mixture stirred at room temperature for 2 hours. The solvents were removed in vacuo to give the product as a syrup which formed a foam out of Et₂ O (0.078 g, 87%);

IR (film): 3358, 2254, 1718, 1457 cm⁻¹ ; NMR (CDCl₃): δ 3.27 (1H, d, J=6.2 Hz, CHHCN); 3.32 (1H, d, J=8.8 Hz, CHHCN); 3.53-3.63 (2H, m, CH₂ indole); 3.70 (3H, s, CO₂ CH₃); 5.11 (1H, d, J=12.1 Hz, OCHHPh); 5.21 (1H, d, J=12.1 Hz, OCHHPh); 5.87 (1H, s, NHCOO); 7.22-7.45 (10H, m, indole, C₆ H₅); 8.17 (1H, d, J=8.2 Hz, indole-NH);

Step 8

LiOH-H₂ O (0.040 g, 0.95 mmol) was added to a stirred solution of the methylester (0.070 g, 0.19 mmol) in THF:H₂ O (4 mL, 3:1 mixture) at room temperature. The mixture was stirred at room temperature for 16 hours and the THF removed in vacuo. The residue was diluted with water (10 mL) and extracted once with Et₂ O (10 mL). The aqueous solution was made pH 4 with 5% citric acid solution and the product extracted into EtOAc (3×10 mL). The combined EtOAc extracts were dried over MgSO₄, filtered, and the solvent removed in vacuo giving the product as a foam (0.045 g, 65%);

IR (film): 3401, 2586, 1712 cm⁻¹ ; NMR (CDCl₃): δ 3.25-3.37 (3H, m, CH₂ CN, CHH indole); 3.54-3.59 (1H, m, CHH indole); 5.05 (1H, d, J=12.3 Hz, OCHHPh); 5.14 (1H, d, J=12.1 Hz, OCHHPh); 5.76 (1H, b, NHCOO); 6.89 (1H, s, indole-H₂); 7.02-7.16 (2H, m, indole-H₅ H₆); 7.28-7.31 (6H, m, indole, C₆ H₅); 7.58 (1H, d, J=7.7 Hz, indole); 8.24 (1H, s, indole-NH);

Step 9

N,N'-dicyclohexylcarbodiimide (0.028 g, 0.138 mmol) was added to a stirred solution of the acid (0.045 g, 0.125 mmol) and 1-hydroxybenzotriazole monohydrate (0.023 g, 0.150 mmol) in EtOAc (2 mL). The mixture was stirred for 2 hours at room temperature and the N,N'-dicyclohexylurea filtered off. A solution of (S)-(-)-α-methylbenzylamine (0.023 g, 0.188 mmol) in EtOAc (0.5 mL) was added and the mixture stirred at room temperature for 21 hours. The mixture was filtered and diluted with EtOAc (25 mL) and the EtOAc solution washed with 5% citric acid solution (2×10 mL), once with saturated NaHCO₃ solution (10 mL), and once with brine (10 mL). The EtOAc solution was dried over MgSO₄, filtered, and solvent removed in vacuo. The residue was purified by chromatography on silica using 67% n-hexane/33% EtOAc as eluant giving the product as a white amorphous solid (0.023 g, 40%);

IR (film): 3337, 3033, 2931, 2251, 1717, 1656, 1496, 1257 cm⁻¹ ; NMR (CDCl₃): δ 0.98 (1.5H, d, J=6.7 Hz, 0.5 CH₃); 1.29 (1.5H, d, J=7.4 Hz, 0.5 CH₃); 3.16-3.57 (4H, m, indole CH₂, CH₂ CN); 4.82-4.95 (1H, m, PhCHNHCO); 5.01-5.19 (2H, m, CH₂ Ph); 5.55 (1H, d, J=8.9 Hz, NHCOO); 6.03 (0.5H, d, J=7.3 Hz, 0.5 CONH); 6.12 (0.5H, d, J=7.7 Hz, 0.5 CONH); 6.56 (0.5H, s, 0.5 indole-H₂); 6.97-7.37 (13.5H, m, Ar); 7.54-7.61 (1H, m, Ar); 7.98 and 8.29 (1H, two s, indole-NH). Analysis calculated for C₂₉ H₂₈ N₄ O₃ : C, 72.48; H, 5.87; N, 11.66%. Found: C, 72.29; H, 5.97; N, 11.48%.

EXAMPLE 63 Carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]-, 2-benzofuranylmethyl ester, [R-(R*,S*)] ##STR114## Step 1

To a stirred solution of 2-benzofuranylmethanol (Garter R, J Am Chem Soc 1951;73:4400) (1.48 g, 10 mmol) and 4-nitrophenylchloroformate (2.01 g, 10 mmol) in CH₂ Cl₂ (50 mL, a) at 0° C. was added dropwise a solution of pyridine (0.79 g, 10 mmol) in CH₂ Cl₂ (10 mL). The reaction mixture was allowed to warm to room temperature overnight. The solvent removed under reduced pressure and the residue taken up between EtOAc (50 mL) and 10% citric acid solution (50 mL). The organic phase was washed successively with 10% citric acid solution (2×50 mL), H₂ O (50 mL), saturated NaHCO₃ solution (5×50 mL), brine (50 mL), dried (MgSO₄), filtered, and solvent removed under reduced pressure. The product was then recrystallized from Et₂ O to give pure carbonate (1.80 g, 58%);

mp 90.5-92.5° C.; ¹ H NMR (CDCl₃): δ 5.41 (2H, s, CH₂ O); 6.90 (1H, s, benzofuran C3-H); 7.21-7.42 (2H, m, ArH); 7.39 (2H, d, 9.2 Hz, ArH's meta to NO₂); 7.52 (1H, d, 7.8 Hz, ArH); 7.60 (1H, d, 7.1 Hz, ArH); 8.28 (2H, d, 9.2 Hz, ArH's ortho to NO₂); IR (film): 3119, 1770, 1617, 1594, 1524 cm⁻¹ ; MS m/e (CI) 313; Analysis calculated for C₁₆ H₁₁ NO₆ (C,H,N).

Step 2

To a stirred solution of the carbonate (185 mg, 0.6 mmol) and α-methyltryptophanyl-1-phenethylamide (160 g, 0.5 mmol) in DMF (5 mL) was added 4-dimethylaminopyridine (61 mg, 0.5 mmol) and the mixture left to stir overnight at room temperature. The solvent was removed at 60° C. under reduced pressure, the residue taken up in EtOAc (100 mL) and washed successively with 10% citric acid solution (3×30 mL), H₂ O (30 mL), 1N NaOH (5×30 mL), brine (2×50 mL), dried (MgSO₄), filtered, and the solvent removed under reduced pressure. The residue was then purified by chromatography on reverse phase silica eluting with 35% H₂ O in MeOH. Crystallization from Et₂ O gave pure product (140 mg, 56%); mp 103-111° C.;

¹ H NMR (CDCl₃): δ 1.31 (3H, d, 6.9 Hz, CHCH₃); 1.63 (3H, s, CCH₃); 3.25 (1H, d, 14.8 Hz, CHH-indole); 3.47 (1H, d, 14.8 Hz, CHH-indole); 4.95-5.05 (1H, m, NHCHCH₃); 5.14 and 5.21 (each 1H, each d, 13.2 Hz, CHHO); 5.41 (1H, s, OCONH); 6.30-6.35 (1H, bd, CONHCH); 6.74 (1H, s, benzofuran C3-H); 6.78 (1H, d, 2.3 Hz, indole C2-H); 7.05-7.33 (10H, m, ArH); 7.45 (1H, d, 8.4 Hz); 7.52-7.58 (2H, m, ArH); 7.85 (1H, s, indole NH);

[α]_(D) =+17.6° C. (c=0.5, 21° C., MeOH); IR (film): 3334, 1715, 1651 cm⁻¹ ; MS m/e (FAB) 496.3 (M⁺ +H); Analysis calculated for C₃₀ H₂₉ N₃ O₄ (C,H,N).

EXAMPLE 64 Carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[(1-phenylethyl)amino]ethyl]-, benzo[b]thien-2-yl-methyl ester, [R-(R*,S*)]- ##STR115## Step 1

Method as for Example 63 using benzo[b]thiophene-2-methanol (Blicke F F, Sheets D G. J Am Chem Soc. 1949;71:2856) (1.64 g, 10 mmol). On removal of ethylacetate under reduced pressure, a crystalline solid formed. This was washed with ether to give carbonate (1.78 g, 54%); mp 119-121.5° C.;

¹ H NMR (CDCl₃): δ 5.54 (2H, s, CH₂ O); 7.34-7.45 (3H, m, ArH); 7.39 (2H, d, 9.1 Hz, ArH's meta to NO₂); 7.74-7.90 (2H, m, ArH); 8.28 (2H, d, 9.2 Hz, ArH's ortho to NO₂); IR (film): 3083, 1763, 1616, 1593, 1523, 1349, 1214, 860 cm⁻¹ ; MS m/e (CI) 329; Analysis calculated for C₁₆ H₁₁ NO₅ S (C,H,N,S).

Step 2

Method as for Example 63 using 198 mg (0.6 mmol) of carbonate. The crude product was purified using normal phase silica eluting with 40% EtOAc in hexane. Crystallization from Et₂ O gave pure product (236 mg, 92%); mp 146-150° C.;

¹ H NMR (CDCl₃): δ 1.28 (3H, d, 6.9 Hz, CHCH₃); 1.64 (3H, s, CCH₃); 3.25 (1H, d, 14.8 Hz, CHH-indole); 3.47 (1H, d, 14.8 Hz, CHH-indole); 4.95-5.05 (1H, m, NHCHCH₃); 5.27 (1H, d, 13.0 Hz, CHHO); 5.34 (1H, d, 13.1 Hz, CHHO); 5.42 (1H, s, OCONH); 6.28-6.35 (1H, bd, CONHCH); 6.78 (1H, s, indole C₂ -H); 7.05-7.35 (11H, m, ArH); 7.58 (1H, d, 7.9 Hz, indole C₄ -H); 7.70-7.80 (2H, m, ArH); 7.89 (1H, s, indole NH); [α]_(D) =+18° C. (c=0.5, 19° C., MeOH); IR (film): 3344, 1714, 1651, 1494, 1456, 1249, 1128, 1067, 744 cm⁻¹ ; MS m/e (FAB) 512.2 (M⁺ +H); Analysis calculated for C₃₀ H₂₉ N₃ O₃ S (C,H,N,S).

EXAMPLE 65 [2-(1H-Indol-3-yl)-1-methyl-1-(1-phenyl-ethyl-carbamoyl)-ethyl]-carbamic acid 2-fluoro-5-methyl-benzyl ester ##STR116## Step 1

A solution of 2-fluoro-5-methylbenzoic acid (2 g, 13 mmol) in THF (30 mL) was added slowly to a stirred suspension of NaBH₄ (593 mg, 15.6 mmol) in THF (30 mL) at room temperature under nitrogen. The mixture was stirred until effervescence ceased, before iodine was added slowly (1.65 g, 6.5 mmol) to the reaction mixture. The reaction mixture was stirred for a further 72 hours during which time an extra equivalent each of NaBH₄ and iodine were added to cause the reaction to go to completion. 2 M HCl (5 mL) was carefully added to the reaction mixture under nitrogen. Ether was then added and the organic phase was separated from the aqueous phase. This was washed with NaHCO₃ (aq), water, dried (MgSO₄) and concentrated in vacuo. The residue was purified by silica gel flash chromatography, eluting with a gradient of hexane to hexane:EtoAc (9:1) to provide the alcohol as a clear oil (1.42 g, 78% yield);

¹ H NMR (CDCl₃): δ 2.28 (3H, s, CH₃); 2.37 (1H, Bs, OH); 4.65 (2H, d, J=4.8 Hz, CH₂ OH); 6.86-6.91 (1H, m, ArH); 6.99-7.03 (1H, m, ArH); 7.15-7.17 (1H, m, ArH); IR (film): 3346, 2926 (sm), 2886 (sm), 1501, 1457 (sm), 1247, 1228, 1205, 1140, 1121, 1042, 1020, 814 cm⁻¹ ; MS m/e (CI) M=140;

Step 2

The alcohol was converted to the carbonale via the method used for Example 63;

¹ H NMR (CDCl₃): δ 2.32 (3H, s, CH₃); 5.31 (2H, s, CH₂ O); 6.96-7.0 (1H, m, ArH of F-Ph); 7.13-7.16 (1H, m, ArH of F-Ph); 7.21-7.23 (1H, m, ArH of F-Ph); 7.35-7.39 (2H, m, 2ArH of P-NO₂ Ph); 8.22-8.27 (2H, m, 2ArH of p-NO₂ Ph); IR (film): 1767, 1617 (sm), 1594 (sm), 1525, 1504, 1348, 1210, 1164, 862 cm⁻¹ ; MS m/e (CI) 306=M+H⁺.

Step 3

The carbonate (366 mg, 1.2 mmol), the α-methyl tryptophonyl-1-phenethylamide (385 mg, 1.2 mmol) and dimethylaminopyridine (147 mg, 1.2 mmol) were stirred in DMF (100 mL) at room temperature overnight. The reaction mixture was taken up in EtoAc and washed with NaHCO₃ (aq), Na₂ CO₃ (aq), 1N HCl, dried (MgSO₄) and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with 7:3 hexane:EtoAc to give 9 (iii) as a white solid (0.195 g, 77%); mp 104-106° C.;

¹ H NMR (CDCl₃): 1.28 (3H, d, J=7.2 Hz, NHCHCH₃); 1.60 (3H, s, αMe); 2.26 (3H, s, Ph-CH₃); 3.24 (1H, d, J=14.8 Hz, CHH indole); 3.45 (1H, d, J=14.8 Hz, CHHindole); 4.95-5.03 (1H, m, NHCHCH₃ ; 5.06 and 5.12 (2H, 2× d, J=12.5 and 12.0 Hz, CH₂ OCONH 5.3-5.4 (1H, m, OCONH); 6.34 (1H, bd, J=7.8 Hz, CONHCH); 6.79-7.32 (12H, m, 12 ArH); 7.56 (1H, d, J=8.1 Hz, ArH); 7.90-7.95 (1H, Bs, NHindole); [α]_(D) ²³.2° C. =+7.74° C. (C=0.155 g 100 mL⁻¹, MeOH); IR (film): 3334, 2927, 1715, 1652, 1505, 1456, 1251, 1072, 743 cm⁻¹ ; MS m/e (FAB): 488.3=M+H⁺ ; Analysis calculated for C₂₉ H₃₀ FN₃ O₃ (C,H,N).

EXAMPLE 66 Carbamic acid, [1-(1H-indol-3-ylmethyl)-1-methyl-2-oxo-2-[[1-(4-pyridinyl)ethyl]amino]ethyl]-, 2-benzofuranyl-methyl ester, monohydrochloride, [R-(R*,S*)] ##STR117## Step 1

To a suspension of lithium aluminum hydride (2.82 g, 63 mmol) in dry THF (150 mL) at -50° C. under nitrogen was added dropwise a solution of benzofuran-2-carboxylic acid (10.2 g, 63 mmol) in THF (100 mL). The reaction mixture was allowed to warm to room temperature and stirred for 16 hours. 1N HCl was added slowly with cooling (cardice-acetone bath) and the resulting solution was washed with 1N HCl, NaHCO₃(aq), dried (MgSO₄) and the solvent removed in vacuo. The residue was purified by flash chromatography on silica eluting with a mixture of hexane:EtOAc (1:1) to give the alcohol as a yellow oil (7.2 g, 77%);

¹ H NMR (CDCl₃): δ 2.68 (1H, s, OH); 4.70 (2H, s, CHHOH); 6.58 (1H, s, ArH3); 7.15-7.27 (2H, m, ArH); 7.42 (1H, d, 8.1 Hz, ArH); 7.48-7.51 (1H, m, ArH); Analysis calculated for C₉ H₈ O₂ (C,H,N).

Step 2

To a stirred solution of the alcohol from Step 1 (8.58 g, 58 mmol) and pyridine (4.82 mL, 58 mmol) in CH₂ Cl₂ (150 mL) at 10° C. was added dropwise a solution of p-nitrophenyl chloroformate (14 g, 70 mmol) in CH₂ Cl₂ (150 mL). The reaction mixture was allowed to warm to room temperature and stirred for 18 hours. The solvent was removed in vacuo and the residue taken up in EtOAc, washed with 1N HCl, NaHCO₃ (aq), dried (MgSO₄) and concentrated in vacuo. The resultant yellow solid was purified using hexane:ether (9:1) as eluant to give the carbonate as a cream solid (9.8 g, 54%);

IR (film): 3119, 1770, 1617, 1594, 1524, 1346, 1251, 1213, 862, 753 cm⁻¹ ; mp 90.5-92.5° C.; ¹ H NMR (CDCl₃): δ 5.41 (2H, s, CHHO); 6.90 (1H, s, H2 of benzofuran); 7.21-7.42 (2H, m, ArH); 7.39 (2H, d, 9.2 Hz, H2, H6 of phenyl); 7.52 (1H, d, 7.8 Hz, ArH); 7.60 (1H, d, 7.1 Hz, ArH); 8.28 (2H, d, 9.2 Hz, H3, H5, of phenyl); Analysis calculated for C₁₆ H₁₁ NO₆ (C,H,N).

Step 3

The mixed carbonate from Step 2 (7 g, 22 mmol), (R)α-methyltryptophan, methyl ester (5.2 g, 22 mmol), and dimethylaminopyridine (2.7 g, 22 mmol) were stirred in DMF (60 mL) at room temperature overnight. The reaction mixture was taken up in ether, washed with NaCO₃(aq), 1N HCl, dried (MgSO₄) and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with hexane:EtOAc (7:3) to give the urethane as a yellow sticky solid (8.57 g, 96%);

¹ H NMR (CDCl₃): δ 1.70 (3H, s, α CH₃); 3.36 (1H, d, 14.6 Hz, CHH indole); 3.54 (1H, bd, 13.9 Hz, CHH indole); 3.67 (3H, s, CO₂ CH₃); 5.17 (1H, d, 13.4 Hz, CHHOCONH); 5.27 (1H, d, 13.2 Hz, CHHOCONH); 5.58 (1H, bs, OCONH); 6.78 (1H, s, ArH); 6.81 (1H, s, ArH); 7.00 (1H, t, 7.6 Hz, ArH); 7.12 (1H, t, 7.3 Hz, ArH); 7.23-7.34 (3H, m, ArH); 7.47-7.50 (2H, m, ArH); 7.81 (1H, bs, indole NH).

Step 4

To a solution of the urethane (8.57 g, 21 mmol) in THF (90 mL) was added lithium hydroxide (30 mL, 10 M), methanol (30 mL) and water (60 mL) and the reaction was stirred at room temperature for 2 days. The volatiles were removed in vacuo and the aqueous mixture was acidified with 1N HCl, and extracted with EtOAc. The organic phase was washed with water, dried (MgSO₄) and concentrated in vacuo to yield the acid as a yellow oil (8.23 g, 100%) which was used without further purification in the next step.

Step 5

To a solution of the acid (8.23 g, 21 mmol) in EtOAc was added dicyclohexylcarbodiimide (4.3 g, 21 mmol) followed by pentafluorophenol (3.86 g, 21 mmol) and the mixture was stirred at room temperature for 16 hours. The mixture was cooled to 0° C. for 30 minutes and the resulting precipitate of dicyclo hexylurea was removed by filtration. The filtrate was washed with 1N HCl, NaCO₃(aq), dried (MgSO₄) and the solvents removed in vacuo. The residue was purified by flash chromatography on silica gel eluting with a mixture of hexane:EtOAc (9:1) to give the pentafluorophenyl ester as a cream solid (7.5 g, 64%).

IR (film): 3418, 1785, 1707, 1652, 1520, 1455, 1254 cm⁻¹ ; MS m/e (CI): 559 (M+H); ¹ H NMR (CDCl₃): δ 1.74 (3H, s, α CH₃); 3.44 (1H, d, 14.9 Hz, CHH indole); 3.66 (1H, d, 14.6 Hz, CHH indole); 5.18-5.29 (3H, m, CHHOCONH); 6.79 (1H, s, ArH); 7.0 (1H, s, ArH); 7.04 (1H, t, 7.6 Hz, ArH); 7.18 (1H, t, 7.5 Hz, ArH); 7.21-7.36 (3H, m, ArH); 7.46 (1H, d, 8.1 Hz, ArH); 7.55-7.58 (2H, m, ArH); 8.02 (1H, bs, indole NH); Analysis calculated for C₂₈ H₁₉ F₅ N₂ O₅ (C,H,N).

Step 6

Hydroxyl amine sulfate (11.13 g, 68 mmol) and potassium hydroxide (7.58 g, 135 mmol) as aqueous solutions, were added in quick succession to a methanolic solution (100 mL) of 4-acetylpyridine (2.73 g, 23 mmol) and the mixture was stirred overnight. The solvent was removed and the residue was taken up in EtOAc and washed with water, dried (MgSO₄) and concentrated in vacuo. The resulting solid was washed with ether and dried to yield the oxime as a solid (2.25 g, 72%).

Step 7

To a solution of the oxime (2.079 g, 15.3 mmol) in methanol (50 mL) was added Pearlman's catalyst: in methanol (2 micro spatulas in 5 mL). The reaction mixture was shaken under a hydrogen pressure of 46 psi and at 30° C. in a Parr Apparatus for 18 hours. The reaction mixture was filtered through Keiselguhr and the filtrate concentrated in vacuo to yield a racemic mixture of the free amine. The amine was taken up in methanol (5 mL) and one equivalent of (S)-tartaric acid (2.3 g, 15.3 mmol) in H₂ O (3 mL) was added. The tartrate salt was filtered off and recrystallized in aqueous methanol twice to yield the (S)(S) tartrate salt of the amine homochirally pure (H₂ O, C=0.625 g 100 mL⁻¹). The tartrate salt of the amine ([s] [s]) was taken up in water, basified to pH 14 and re-extracted with EtOAc. The organic layer was dried and concentrated in vacuo to yield the free amine;

[α]_(D) ²⁰.6 =23.12 (EtOH). (J Am Chem Soc 95:7525 (1973))

Step 8

The pentafluorophenyl ester from Step 5 (335 mg, 0.6 mmol) and the amine from Step 7 (73 mg, 0.6 mmol) were stirred at room temperature in DMF (80 mL) for 24 hours. The reaction mixture was washed with NaHCO₃(aq), brine, dried (MgSO₄) and concentrated in vacuo. The residue was purified by silica gel flash chromatography, eluting with a gradient of hexane:EtoAc (6:4) to hexane:EtoAc (2:8). The amide was obtained as a white solid (165 mg, 55%); mp 198.5-199.5° C.;

[α]_(D) ²¹.1° C. =+34.62 (c=0.065 g 100 mL⁻¹, MeOH); IR (film): 3395, 3322, 1715, 1645, 1521, 1455, 1253, 1070 cm⁻¹ ; MS m/e (FAB): 497.3=M+H⁺ ; ¹ H NMR (CDCl₃): δ 1.28 (3H, d, J=6.8 Hz, CHCH₃); 1.62 (3H, s [obscured by water peak], αCH₃); 3.22 (1H, d, J=14.8 Hz, CHH indole); 3.53 (1H, d, J=14.8 Hz, CHH indole); 4.91-5.00 (1H, m, NHCH Pyr); 5.17 (1H, d, J=13.4 Hz, CHHOCONH); 5.25 (1H, d, J=13.2 Hz, CHHOCONH); 5.33 (1H, s, OCONH); 6.49 (1H, bd, NHCHCH₃); 6.79 (2H, d, J=12 Hz, 2ArH); 7.06-7.36 (7H, m, 7ArH); 7.46 (1H, d, J=8.4 Hz, 1ArH); 7.56 (2H, d, J=8 Hz, 2ArH); 7.97 (1H, s, indole NH); 8.47 (2H, d, J=4.4 Hz, 2Ar pyridyl protons); Analysis calculated for C₂₉ H₂₈ N₄ O₄ (C,H,N).

Step 9

To a solution of the pyridine derivative from Step 8 in EtOAc was added over one equivalent of HCl in dioxan (2 mL, 4 M) causing the hydrochloride salt to precipitate out. The salt was filtered and washed thoroughly with ether before repeated triturations with EtOAc/ether mixtures yielded the hydrochlorine salt as a white solid (0.134 g, 45%); mp 125-128° C.;

[α]_(D) ²³.0° C. =+57.5 (c=0.08 g 100 mL⁻¹, MeOH); IR (film): 3270, 3060, 1710, 1660, 1614, 1505, 1455, 1362, 1251, 1070 cm⁻¹ ; MS m/e (FAB): 497.4=M+H⁺ -Cl; ¹ H NMR (DMSO): δ 1.31 (3H, s, CHCH₃); 1.33 (3H, s, αCH₃); 3.13 (1H, d, J=14.4 Hz, CHH indole); 3.33-3.38 (1H, m, CHH indole); 4.98-5.07 (1H, m, NHCHCH₃); 5.19 (2H, 2×d, no J value available, CH₂ OCONH); 6.82 (1H, t^(t), J=7.6 and 7.2 Hz, ArH); 6.95-6.97 (2H, m, 2ArH); 7.2-7.38 (4H, m, 4ArH); 7.40 (1H, d, J=8 Hz, ArH); 7.52 (1H, d, J=8.4 Hz, ArH); 7.61 (1H, d, J=8 Hz, ArH); 7.91 (1H, d, J=5.2 Hz, ArH); 8.36 (1H, d, J=6.8 Hz, CONHCH); 8.78 (2H, d, J=5.6 Hz, H² and H⁶ of pyridine); 10.89 (1H, s, indole NH); Analysis calculated for C₂₉ H₂₉ ClN₄ O₄.0.85 H₂ O (C,H,N).

EXAMPLE 67 Carbamic acid, [1-(1H-indol-3-ylmethyl)-2-[methyl-(phenylmethyl)amino]-2-oxoethyl]-, 2-benzofuranylmethyl ester, (S)- ##STR118## Step 1

To a stirred solution of Boc-(S)-tryptophan-O-succinimidyl ester (5.1 g, 12.6 mmol) in ethyl acetate (150 mL) at room temperature was added N-methyrlbenzylamine (1.68 g, 13.9 mmol) in ethyl acetate (50 mL) dropwise. The mixture was stirred at room temperature for 120 hours and then washed with 1N HCl (aq), NaHCO₃ (aq), brine, dried (MgSO₄), and concentrated in vacuo. The residue was chromatographed on silica gel using a gradient of 10% ether in dichloromethane to 50% ether in dichloromethane to elute the pure compound. Concentration in vacuo gave the product as a white foam (5.13 g, 95%); mp 56-58° C.;

IR (film): 3303, 1699, 1635 cm⁻¹ ; ¹ H NMR (CDCl₃): δ 1.41 (3H, s, t-Bu); 1.44 (6H, s, t-Bu); 2.55 (2H, s, N-Me); 2.75 (1H, s, N-Me); 3.19 (2H, d, 7 Hz, β-CH₂); 3.96 (0.3H, d, 16 Hz, CH₂ Ph); 4.34 (0.3H, d, 16 Hz, CH₂ Ph), 4.43 (1.4H, s, CH₂ Ph); 5.00 (1H, m, α-H); 5.47 (1H, m, OCONH); 6.90-7.35 (9H, m, aromatics); 7.54 (0.33H, d, 7.5 Hz, aromatics); 7.68 (0.66H, d, 7.5 Hz, aromatics); 7.98 (0.66H, s, indole NH); 8.04 (0.33H, s, indole NH); Analysis calculated for C₂₄ H₂₉ N₃ O₃.0.25 EtoAc C,H,N).

Step 2

Boc-(S)-tryptophan-N-methylbenzylamide (5.00 g, 12.3 mmol) was dissolved in a mixture of trifluoroacetic acid:water (9:1) (50 mL) and stirred for 45 minutes at room temperature. The solvent was removed in vacuo, the residue taken up in ethyl acetate (100 mL), washed with NaHCO₃ (aq), brine, dried (MgSO₄) and concentrated in vacuo. The residue was chromatographed on silica gel, eluting with methanol:dichloromethane (10-20%, 60 minutes) to give the product as a white solid (2.60 g, 69%);

mp 118-122° C.; IR (film): 3290, 1633 cm⁻¹ ; ¹ H NMR (CDCl₃): δ 2.74 (2H, s, N-Me); 2.92 (1H, s, N-Me); 2.98 (1H, m, β-CH₂); 3.17 (1H, m, β-CH₂); 3.98 (0.33H, t, 7 Hz, α-H); 4.11 (0.66H, t, 7 Hz, α-H); 4.20 (0.5H, d, 17 Hz, CH₂ Ph); 4.44 (0.5H, d, 17 Hz, CH₂ Ph); 4.49 (0.5H, d, 14.5 Hz, CH₂ Ph); 4.60 (0.5H, d, 14.5 Hz, CH₂ Ph); 7.01-7.37 (10.3H, m, aromatics); 7.59 (0.66H, d, 8 Hz, aromatics); 8.20 (1H, s, indole NH); Analysis calculated for C₁₉ H₂₁ N₃ O.0.3 H₂ O (C,H,N).

Step 3

To a stirred solution of 2-benzofuranyl p-nitrophenyl carbonate (157 mg, 0.5 mmol) in DMF (3 mL) was added (S)-tryptophan-N-methylbenzylamide (154 mg, 0.5 mmol) in DMF (2 mL) and stirring continued overnight at room temperature. The solvent was removed in vacuo and the residue taken up in ethyl acetate, washed with 1N HCl (aq), NaHCO₃ (aq), brine, dried (MgSO₄) and concentrated in vacuo. The residue was chromatographed on reverse phase silica (C18) using a gradient of 70% to 90% acetonitrile in water (0.1% TFA) to elute the pure compound (93 mg, 39%); mp 63-65° C.;

IR (film): 3296, 1714, 1634 cm⁻¹ ; MS m/e (FAB): 482.6=M+H; ¹ H NMR (CDCl₃): δ 2.48 (2H, m, N-Me); 2.80 (1H, m, N-Me); 3.20 (2H, m, β-CH₂); 3.98 (0.5H, d, 16.5 Hz, CH₂ Ph); 4.37 (0.5H, d, 16.5 Hz, CH₂ Ph); 4.40 (0.5H, d, 15 Hz, CH₂ Ph); 4.47 (0.5H, d, 15 Hz, CH₂ Ph); 5.11 (1H, m, α-H); 5.22 (2H, m, ArCH₂ O); 5.78 (1H, m, OCONH); 6.70-7.69 (15H, m, aromatics); 7.87 (0.5H, s, indole NH); 7.95 (0.5H, s, indole NH); Analysis calculated for C₂₉ H₂₇ N₃ O₄ (C,H,N).

EXAMPLE 68 Carbamic acid, [1-(1H-indol-3-ylmethyl)-2-[methyl-(phenylmethyl)amino]-2-oxoethyl]-, benzo[b]thien-2-ylmethyl ester, (S)- ##STR119##

To a stirred solution of 2-benzothiophenyl p-nitrophenyl carbonate (165 mg, 0.5 mmol) in DMF (3 mL) was added (S)-tryptophan-N-methylbenzylamide (154 mg, 0.5 mmol) in DMF (2 mL) and stirring continued overnight at room temperature. The solvent w,as removed in vacuo and the residue taken up in ethyl acetate, washed with 1N HCl (aq), NaHCO₃ (aq), brine, dried (MgSO₄), and concentrate in vacuo. The residue was chromatographed on reverse-phase silica (C18) using a gradient of 70% to 90% acetonitrile in water (0.1% TFA) to elute the pure compound (72 mg, 29%); mp 64-67° C.;

IR (film): 3292, 1713, 1634 cm⁻¹ ; MS m/e (FAB): 5020.6=M+Na⁺¹ NMR (CDCl₃): δ 2.50 (2H, m, N-Me); 2.78 (1H, m, N-Me); 3.20 (2H, m, β-CH₂); 3.96 (0.5H, d, 16 Hz, H₃ CH₂ Ph); 4.35 (0.5H, d, 16 Hz, CH₂ Ph); 4.41 (0.5H, d, 15 Hz, CH₂ Ph); 4.46 (0.5H, d, 15 Hz, CH₂ Ph); 5.05 (1H, m, α-H); 5.33 (2H, m, ArCH₂ O); 5.78 (1H, m, OCOHN); 6.80-7.83 (15H, m, aromatics); 7.86 (0.5H, s, indole NH); 7.93 (0.5H, s, indole NH); Analysis calculated for C₂₉ H₂₇ N₃ O₃ S.0.2 H₂ O (C,H,N,S). 

We claim:
 1. A compound selected from the group consisting of:(R)-Trp (S)-NHCH(CH3)-phenyl, (R)-α-MeTrp (S)-NHCH(CH₃)-phenyl, and (S)-Trp N(CH₃)CH₂ -phenyl.
 2. A compound of formula ##STR120## wherein R is phenyl, pyridine,thiophene, furan, naphthalene, indole, benzofuran, or benzothiophene each unsubstituted, mono-, di-, or trisubstituted byalkyl hydroxy, alkoxy, NO₂, halogen, NH₂, or CF₃ ; R¹ and R² are each independently hydrogen or alkyl of from 1 to 4 atoms; and R and R², when joined by a bond, may form a ring. 